Understanding tc qdisc and iperf Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern) 2019 Community Moderator Election Results Why I closed the “Why is Kali so hard” questionHaving several qdisc for each device, which is the first to process?Xen and traffic shapingGet list of qdiscs and filters that are supported by tc toolUsing qdisc prio under htb classI want to limit a SFQ qdisc by bytesHTB traffic shaper - download speed degradeTC (Traffic control) and trickle: apply different bandwidth to (multiple requests) same IP or URL during upload and downloadHow can I permanently associate tc qdisc commands with a particular interface?htb -> netem -> pfifo_fast qdisc drops all packets under high traffictc-netem ignores set rate limit and packet reordering

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Understanding tc qdisc and iperf



Announcing the arrival of Valued Associate #679: Cesar Manara
Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)
2019 Community Moderator Election Results
Why I closed the “Why is Kali so hard” questionHaving several qdisc for each device, which is the first to process?Xen and traffic shapingGet list of qdiscs and filters that are supported by tc toolUsing qdisc prio under htb classI want to limit a SFQ qdisc by bytesHTB traffic shaper - download speed degradeTC (Traffic control) and trickle: apply different bandwidth to (multiple requests) same IP or URL during upload and downloadHow can I permanently associate tc qdisc commands with a particular interface?htb -> netem -> pfifo_fast qdisc drops all packets under high traffictc-netem ignores set rate limit and packet reordering



.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;








15















I'm trying to limit bandwidth with tc and check the results with iperf. I started like this:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35213 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 830 MBytes 696 Mbits/sec


The two instances are directly connected with through Ethernet.



I then set up a htb qdisc with one default class to limit bandwidth to 1mbit/sec:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit


But I don't get what I expect:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35217 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-12.8 sec 768 KBytes 491 Kbits/sec


If I double the rate, the measured bandwidth does not change. What am I missing? Why doesn't the the measured bandwidth correspond to the 1mbit from the rate parameter? What parameters do I need to set to limit the bandwidth to an exact given rate?



However, the man page says that tbf should be the qdisc of choice for this task:




The Token Bucket Filter is suited for slowing traffic down to a precisely configured rate. Scales well to large bandwidths.




tbf requires parameters rate, burst and (limit| latency). So I tried the following without understanding how burst and (limit| latency) affect the available bandwidth:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k


This got me a measured bandwidth of 113 Kbits/sec. Playing around with those parameters didn't change that much until I noticed that adding a value for mtu changes things drastically:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k mtu 5000


resulted in a measured bandwidth of 1.00 Mbits/sec.



What parameters would I need to set to limit the bandwidth to an exact given rate?



Should I use the htb or tbf queueing discipline for this?



EDIT:



Based on these resources, I have made some tests:



  • https://help.ubuntu.com/community/UbuntuBonding

  • https://help.ubuntu.com/community/LinkAggregation

  • /usr/share/doc/ifenslave-2.6/README.Debian.gz http://lartc.org/

I have tried the following setups.



On a Physical Machine



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto br0
iface br0 inet dhcp
bridge_ports eth0


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.4 port 51804 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.4 port 51804
[ 4] 0.0-13.7 sec 1.62 MBytes 993 Kbits/sec


On a Virtual Machine without Bonding



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 34347 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.3 sec 1.62 MBytes 1.21 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.7 port 34347
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on eth0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49054 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49054
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on bond0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49055 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-13.3 sec 768 KBytes 475 Kbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49055
[ 4] 0.0-14.1 sec 768 KBytes 446 Kbits/sec


The result does not change if I remove eth1 (the passive interface) from the bond.



Conclusion



Traffic Control on a bond interface does not work, or at least not as expected. I will have to investigate further.



As a workaround one could add the queueing disciplines directly to the interfaces belonging to the bond.










share|improve this question
























  • Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

    – Matías E. Fernández
    May 9 '12 at 18:33






  • 1





    I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

    – derobert
    Oct 22 '12 at 15:37












  • I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

    – user93961
    Dec 5 '14 at 18:49

















15















I'm trying to limit bandwidth with tc and check the results with iperf. I started like this:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35213 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 830 MBytes 696 Mbits/sec


The two instances are directly connected with through Ethernet.



I then set up a htb qdisc with one default class to limit bandwidth to 1mbit/sec:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit


But I don't get what I expect:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35217 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-12.8 sec 768 KBytes 491 Kbits/sec


If I double the rate, the measured bandwidth does not change. What am I missing? Why doesn't the the measured bandwidth correspond to the 1mbit from the rate parameter? What parameters do I need to set to limit the bandwidth to an exact given rate?



However, the man page says that tbf should be the qdisc of choice for this task:




The Token Bucket Filter is suited for slowing traffic down to a precisely configured rate. Scales well to large bandwidths.




tbf requires parameters rate, burst and (limit| latency). So I tried the following without understanding how burst and (limit| latency) affect the available bandwidth:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k


This got me a measured bandwidth of 113 Kbits/sec. Playing around with those parameters didn't change that much until I noticed that adding a value for mtu changes things drastically:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k mtu 5000


resulted in a measured bandwidth of 1.00 Mbits/sec.



What parameters would I need to set to limit the bandwidth to an exact given rate?



Should I use the htb or tbf queueing discipline for this?



EDIT:



Based on these resources, I have made some tests:



  • https://help.ubuntu.com/community/UbuntuBonding

  • https://help.ubuntu.com/community/LinkAggregation

  • /usr/share/doc/ifenslave-2.6/README.Debian.gz http://lartc.org/

I have tried the following setups.



On a Physical Machine



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto br0
iface br0 inet dhcp
bridge_ports eth0


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.4 port 51804 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.4 port 51804
[ 4] 0.0-13.7 sec 1.62 MBytes 993 Kbits/sec


On a Virtual Machine without Bonding



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 34347 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.3 sec 1.62 MBytes 1.21 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.7 port 34347
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on eth0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49054 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49054
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on bond0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49055 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-13.3 sec 768 KBytes 475 Kbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49055
[ 4] 0.0-14.1 sec 768 KBytes 446 Kbits/sec


The result does not change if I remove eth1 (the passive interface) from the bond.



Conclusion



Traffic Control on a bond interface does not work, or at least not as expected. I will have to investigate further.



As a workaround one could add the queueing disciplines directly to the interfaces belonging to the bond.










share|improve this question
























  • Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

    – Matías E. Fernández
    May 9 '12 at 18:33






  • 1





    I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

    – derobert
    Oct 22 '12 at 15:37












  • I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

    – user93961
    Dec 5 '14 at 18:49













15












15








15


6






I'm trying to limit bandwidth with tc and check the results with iperf. I started like this:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35213 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 830 MBytes 696 Mbits/sec


The two instances are directly connected with through Ethernet.



I then set up a htb qdisc with one default class to limit bandwidth to 1mbit/sec:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit


But I don't get what I expect:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35217 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-12.8 sec 768 KBytes 491 Kbits/sec


If I double the rate, the measured bandwidth does not change. What am I missing? Why doesn't the the measured bandwidth correspond to the 1mbit from the rate parameter? What parameters do I need to set to limit the bandwidth to an exact given rate?



However, the man page says that tbf should be the qdisc of choice for this task:




The Token Bucket Filter is suited for slowing traffic down to a precisely configured rate. Scales well to large bandwidths.




tbf requires parameters rate, burst and (limit| latency). So I tried the following without understanding how burst and (limit| latency) affect the available bandwidth:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k


This got me a measured bandwidth of 113 Kbits/sec. Playing around with those parameters didn't change that much until I noticed that adding a value for mtu changes things drastically:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k mtu 5000


resulted in a measured bandwidth of 1.00 Mbits/sec.



What parameters would I need to set to limit the bandwidth to an exact given rate?



Should I use the htb or tbf queueing discipline for this?



EDIT:



Based on these resources, I have made some tests:



  • https://help.ubuntu.com/community/UbuntuBonding

  • https://help.ubuntu.com/community/LinkAggregation

  • /usr/share/doc/ifenslave-2.6/README.Debian.gz http://lartc.org/

I have tried the following setups.



On a Physical Machine



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto br0
iface br0 inet dhcp
bridge_ports eth0


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.4 port 51804 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.4 port 51804
[ 4] 0.0-13.7 sec 1.62 MBytes 993 Kbits/sec


On a Virtual Machine without Bonding



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 34347 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.3 sec 1.62 MBytes 1.21 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.7 port 34347
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on eth0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49054 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49054
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on bond0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49055 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-13.3 sec 768 KBytes 475 Kbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49055
[ 4] 0.0-14.1 sec 768 KBytes 446 Kbits/sec


The result does not change if I remove eth1 (the passive interface) from the bond.



Conclusion



Traffic Control on a bond interface does not work, or at least not as expected. I will have to investigate further.



As a workaround one could add the queueing disciplines directly to the interfaces belonging to the bond.










share|improve this question
















I'm trying to limit bandwidth with tc and check the results with iperf. I started like this:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35213 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 830 MBytes 696 Mbits/sec


The two instances are directly connected with through Ethernet.



I then set up a htb qdisc with one default class to limit bandwidth to 1mbit/sec:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit


But I don't get what I expect:



# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 35217 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-12.8 sec 768 KBytes 491 Kbits/sec


If I double the rate, the measured bandwidth does not change. What am I missing? Why doesn't the the measured bandwidth correspond to the 1mbit from the rate parameter? What parameters do I need to set to limit the bandwidth to an exact given rate?



However, the man page says that tbf should be the qdisc of choice for this task:




The Token Bucket Filter is suited for slowing traffic down to a precisely configured rate. Scales well to large bandwidths.




tbf requires parameters rate, burst and (limit| latency). So I tried the following without understanding how burst and (limit| latency) affect the available bandwidth:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k


This got me a measured bandwidth of 113 Kbits/sec. Playing around with those parameters didn't change that much until I noticed that adding a value for mtu changes things drastically:



# tc qdisc add dev bond0 root tbf rate 1mbit limit 10k burst 10k mtu 5000


resulted in a measured bandwidth of 1.00 Mbits/sec.



What parameters would I need to set to limit the bandwidth to an exact given rate?



Should I use the htb or tbf queueing discipline for this?



EDIT:



Based on these resources, I have made some tests:



  • https://help.ubuntu.com/community/UbuntuBonding

  • https://help.ubuntu.com/community/LinkAggregation

  • /usr/share/doc/ifenslave-2.6/README.Debian.gz http://lartc.org/

I have tried the following setups.



On a Physical Machine



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto br0
iface br0 inet dhcp
bridge_ports eth0


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.4 port 51804 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.4 port 51804
[ 4] 0.0-13.7 sec 1.62 MBytes 993 Kbits/sec


On a Virtual Machine without Bonding



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.7 port 34347 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.3 sec 1.62 MBytes 1.21 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.7 port 34347
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on eth0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev eth0 root handle 1: htb default 12
# tc class add dev eth0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49054 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-11.9 sec 1.62 MBytes 1.14 Mbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49054
[ 4] 0.0-14.0 sec 1.62 MBytes 972 Kbits/sec


On a Virtual Machine with Bonding (tc configured on bond0)



/etc/network/interfaces:



auto lo
iface lo inet loopback

auto eth0
allow-bond0 eth0
iface eth0 inet manual
bond-master bond0
bond-primary eth0 eth1

auto eth1
allow-bond0 eth1
iface eth1 inet manual
bond-master bond0
bond-primary eth0 eth1

auto bond0
iface bond0 inet dhcp
bond-slaves none
bond-mode 1
# bond-arp-interval 250
# bond-arp-ip-target 192.168.2.1
# bond-arp-validate 3


Measurement with iperf:



# tc qdisc add dev bond0 root handle 1: htb default 12
# tc class add dev bond0 parent 1: classid 1:12 htb rate 1mbit
# iperf -c 192.168.2.1
------------------------------------------------------------
Client connecting to 192.168.2.1, TCP port 5001
TCP window size: 23.5 KByte (default)
------------------------------------------------------------
[ 3] local 192.168.2.9 port 49055 connected with 192.168.2.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-13.3 sec 768 KBytes 475 Kbits/sec


Whereas the iperf server calculated a different bandwidth:



[ 4] local 192.168.2.1 port 5001 connected with 192.168.2.9 port 49055
[ 4] 0.0-14.1 sec 768 KBytes 446 Kbits/sec


The result does not change if I remove eth1 (the passive interface) from the bond.



Conclusion



Traffic Control on a bond interface does not work, or at least not as expected. I will have to investigate further.



As a workaround one could add the queueing disciplines directly to the interfaces belonging to the bond.







tc






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited May 9 '12 at 18:27







Matías E. Fernández

















asked May 6 '12 at 15:41









Matías E. FernándezMatías E. Fernández

76114




76114












  • Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

    – Matías E. Fernández
    May 9 '12 at 18:33






  • 1





    I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

    – derobert
    Oct 22 '12 at 15:37












  • I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

    – user93961
    Dec 5 '14 at 18:49

















  • Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

    – Matías E. Fernández
    May 9 '12 at 18:33






  • 1





    I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

    – derobert
    Oct 22 '12 at 15:37












  • I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

    – user93961
    Dec 5 '14 at 18:49
















Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

– Matías E. Fernández
May 9 '12 at 18:33





Strangely enough, this seems to have worked for this guy: blog.tinola.com/?e=22

– Matías E. Fernández
May 9 '12 at 18:33




1




1





I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

– derobert
Oct 22 '12 at 15:37






I think with htb, you have to use tc filter to put the packets into classes. You may also need to change some of the htb parameters (tune it just like tbf). I suggest looking into tcng, which is a front-end to tc. (These are quick pointers...)

– derobert
Oct 22 '12 at 15:37














I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

– user93961
Dec 5 '14 at 18:49





I did not see any filters in your post. What commands are you using to match the traffic so that it can be rate limited?

– user93961
Dec 5 '14 at 18:49










4 Answers
4






active

oldest

votes


















2














When you are unsure about how tc works you can still monitor tc and look how the packets flow? You can use my script to monitor tc and need to run it in a terminal with lifted privilege. You can change wlan0 to another interface and you also need grep and awk:



 #!/bin/sh
INTERVAL=15
while sleep $INTERVAL
do
/usr/sbin/tc -s -d class show dev wlan0

uptime
more /proc/meminfo | grep MemFree | grep -v grep
echo cache-name num-active-objs total-objs obj-size
SKBUFF=`more /proc/slabinfo | grep skbuff | grep -v grep | awk
'print $2 print $3 print $4'`

echo skbuff_head_cache: $SKBUFF
done





share|improve this answer
































    0














    Try increasing the burst/limit values. The token bucket algorithms scale well, but have a limited accuracy/speed ratio.



    Accuracy is achieved by using a small bucket, speed by increasing the size of the tokens. Large tokens mean the rate at which they are replenished is decreased (tokens per second = bytes per second / bytes per token).



    The rate parameter gives the average rate that is not to be exceeded, the burst or limit parameters give the size of the averaging window. As sending out a packet at line speed exceeds the set rate for the time where the packet is transferred, the averaging window needs to be at least large enough that sending a single packet does not push the entire window over the limit; if more packets fit in the window, the algorithm will have a better chance of hitting the target exactly.






    share|improve this answer






























      0














      run this before add queue discipline on bonding interface (bond0 in this case)



      ipconfig bond0 txqueuelen 1000


      it not work because software virtual device like bonding interface has no default queue.






      share|improve this answer






























        0














        Since bond devices doesn't have defined queue, setting the qdisc size explicitly fixes the issue for me.



        Here is an example for a leaf qdisc to be used under HTB structure :
        tc qdisc add dev $dev parent $parent handle $handle pfifo limit 1000






        share|improve this answer























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          4 Answers
          4






          active

          oldest

          votes








          4 Answers
          4






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          2














          When you are unsure about how tc works you can still monitor tc and look how the packets flow? You can use my script to monitor tc and need to run it in a terminal with lifted privilege. You can change wlan0 to another interface and you also need grep and awk:



           #!/bin/sh
          INTERVAL=15
          while sleep $INTERVAL
          do
          /usr/sbin/tc -s -d class show dev wlan0

          uptime
          more /proc/meminfo | grep MemFree | grep -v grep
          echo cache-name num-active-objs total-objs obj-size
          SKBUFF=`more /proc/slabinfo | grep skbuff | grep -v grep | awk
          'print $2 print $3 print $4'`

          echo skbuff_head_cache: $SKBUFF
          done





          share|improve this answer





























            2














            When you are unsure about how tc works you can still monitor tc and look how the packets flow? You can use my script to monitor tc and need to run it in a terminal with lifted privilege. You can change wlan0 to another interface and you also need grep and awk:



             #!/bin/sh
            INTERVAL=15
            while sleep $INTERVAL
            do
            /usr/sbin/tc -s -d class show dev wlan0

            uptime
            more /proc/meminfo | grep MemFree | grep -v grep
            echo cache-name num-active-objs total-objs obj-size
            SKBUFF=`more /proc/slabinfo | grep skbuff | grep -v grep | awk
            'print $2 print $3 print $4'`

            echo skbuff_head_cache: $SKBUFF
            done





            share|improve this answer



























              2












              2








              2







              When you are unsure about how tc works you can still monitor tc and look how the packets flow? You can use my script to monitor tc and need to run it in a terminal with lifted privilege. You can change wlan0 to another interface and you also need grep and awk:



               #!/bin/sh
              INTERVAL=15
              while sleep $INTERVAL
              do
              /usr/sbin/tc -s -d class show dev wlan0

              uptime
              more /proc/meminfo | grep MemFree | grep -v grep
              echo cache-name num-active-objs total-objs obj-size
              SKBUFF=`more /proc/slabinfo | grep skbuff | grep -v grep | awk
              'print $2 print $3 print $4'`

              echo skbuff_head_cache: $SKBUFF
              done





              share|improve this answer















              When you are unsure about how tc works you can still monitor tc and look how the packets flow? You can use my script to monitor tc and need to run it in a terminal with lifted privilege. You can change wlan0 to another interface and you also need grep and awk:



               #!/bin/sh
              INTERVAL=15
              while sleep $INTERVAL
              do
              /usr/sbin/tc -s -d class show dev wlan0

              uptime
              more /proc/meminfo | grep MemFree | grep -v grep
              echo cache-name num-active-objs total-objs obj-size
              SKBUFF=`more /proc/slabinfo | grep skbuff | grep -v grep | awk
              'print $2 print $3 print $4'`

              echo skbuff_head_cache: $SKBUFF
              done






              share|improve this answer














              share|improve this answer



              share|improve this answer








              edited 11 hours ago









              Rui F Ribeiro

              42.1k1484142




              42.1k1484142










              answered Jul 24 '12 at 10:36









              BytemainBytemain

              2,27142232




              2,27142232























                  0














                  Try increasing the burst/limit values. The token bucket algorithms scale well, but have a limited accuracy/speed ratio.



                  Accuracy is achieved by using a small bucket, speed by increasing the size of the tokens. Large tokens mean the rate at which they are replenished is decreased (tokens per second = bytes per second / bytes per token).



                  The rate parameter gives the average rate that is not to be exceeded, the burst or limit parameters give the size of the averaging window. As sending out a packet at line speed exceeds the set rate for the time where the packet is transferred, the averaging window needs to be at least large enough that sending a single packet does not push the entire window over the limit; if more packets fit in the window, the algorithm will have a better chance of hitting the target exactly.






                  share|improve this answer



























                    0














                    Try increasing the burst/limit values. The token bucket algorithms scale well, but have a limited accuracy/speed ratio.



                    Accuracy is achieved by using a small bucket, speed by increasing the size of the tokens. Large tokens mean the rate at which they are replenished is decreased (tokens per second = bytes per second / bytes per token).



                    The rate parameter gives the average rate that is not to be exceeded, the burst or limit parameters give the size of the averaging window. As sending out a packet at line speed exceeds the set rate for the time where the packet is transferred, the averaging window needs to be at least large enough that sending a single packet does not push the entire window over the limit; if more packets fit in the window, the algorithm will have a better chance of hitting the target exactly.






                    share|improve this answer

























                      0












                      0








                      0







                      Try increasing the burst/limit values. The token bucket algorithms scale well, but have a limited accuracy/speed ratio.



                      Accuracy is achieved by using a small bucket, speed by increasing the size of the tokens. Large tokens mean the rate at which they are replenished is decreased (tokens per second = bytes per second / bytes per token).



                      The rate parameter gives the average rate that is not to be exceeded, the burst or limit parameters give the size of the averaging window. As sending out a packet at line speed exceeds the set rate for the time where the packet is transferred, the averaging window needs to be at least large enough that sending a single packet does not push the entire window over the limit; if more packets fit in the window, the algorithm will have a better chance of hitting the target exactly.






                      share|improve this answer













                      Try increasing the burst/limit values. The token bucket algorithms scale well, but have a limited accuracy/speed ratio.



                      Accuracy is achieved by using a small bucket, speed by increasing the size of the tokens. Large tokens mean the rate at which they are replenished is decreased (tokens per second = bytes per second / bytes per token).



                      The rate parameter gives the average rate that is not to be exceeded, the burst or limit parameters give the size of the averaging window. As sending out a packet at line speed exceeds the set rate for the time where the packet is transferred, the averaging window needs to be at least large enough that sending a single packet does not push the entire window over the limit; if more packets fit in the window, the algorithm will have a better chance of hitting the target exactly.







                      share|improve this answer












                      share|improve this answer



                      share|improve this answer










                      answered Jul 24 '12 at 14:08









                      Simon RichterSimon Richter

                      2,5091213




                      2,5091213





















                          0














                          run this before add queue discipline on bonding interface (bond0 in this case)



                          ipconfig bond0 txqueuelen 1000


                          it not work because software virtual device like bonding interface has no default queue.






                          share|improve this answer



























                            0














                            run this before add queue discipline on bonding interface (bond0 in this case)



                            ipconfig bond0 txqueuelen 1000


                            it not work because software virtual device like bonding interface has no default queue.






                            share|improve this answer

























                              0












                              0








                              0







                              run this before add queue discipline on bonding interface (bond0 in this case)



                              ipconfig bond0 txqueuelen 1000


                              it not work because software virtual device like bonding interface has no default queue.






                              share|improve this answer













                              run this before add queue discipline on bonding interface (bond0 in this case)



                              ipconfig bond0 txqueuelen 1000


                              it not work because software virtual device like bonding interface has no default queue.







                              share|improve this answer












                              share|improve this answer



                              share|improve this answer










                              answered Mar 28 '13 at 2:15









                              FanFan

                              1




                              1





















                                  0














                                  Since bond devices doesn't have defined queue, setting the qdisc size explicitly fixes the issue for me.



                                  Here is an example for a leaf qdisc to be used under HTB structure :
                                  tc qdisc add dev $dev parent $parent handle $handle pfifo limit 1000






                                  share|improve this answer



























                                    0














                                    Since bond devices doesn't have defined queue, setting the qdisc size explicitly fixes the issue for me.



                                    Here is an example for a leaf qdisc to be used under HTB structure :
                                    tc qdisc add dev $dev parent $parent handle $handle pfifo limit 1000






                                    share|improve this answer

























                                      0












                                      0








                                      0







                                      Since bond devices doesn't have defined queue, setting the qdisc size explicitly fixes the issue for me.



                                      Here is an example for a leaf qdisc to be used under HTB structure :
                                      tc qdisc add dev $dev parent $parent handle $handle pfifo limit 1000






                                      share|improve this answer













                                      Since bond devices doesn't have defined queue, setting the qdisc size explicitly fixes the issue for me.



                                      Here is an example for a leaf qdisc to be used under HTB structure :
                                      tc qdisc add dev $dev parent $parent handle $handle pfifo limit 1000







                                      share|improve this answer












                                      share|improve this answer



                                      share|improve this answer










                                      answered Mar 18 '15 at 13:21









                                      SagiLowSagiLow

                                      1609




                                      1609



























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