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iperf does not work between VMs

asked 2015-03-04 03:45:48 -0600

fresher gravatar image

updated 2015-03-04 04:59:53 -0600

I have a multinode openstack juno setup. Iperf does not work between VMs( on the same compute node as well as different compute nodes)

On iperf server VM

  iperf -s
    Server listening on TCP port 5001
    TCP window size: 85.3 KByte (default)

On iperf client VM

 iperf -c -p 5001 -i 1 -t 10

The mtu of the VM interface is 1400. It does not work even after increasing or decreasing this value.

eth0      Link encap:Ethernet  HWaddr fa:16:3e:ac:70:99  
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::f816:3eff:feac:7099/64 Scope:Link
          RX packets:5781941 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7096888 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:3028179379 (3.0 GB)  TX bytes:3594331790 (3.5 GB)

Please help me solve this issue.

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2 answers

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answered 2015-03-04 13:52:15 -0600

Iperf uses TCP or UDP depending on the test. Can you ping between the 2 VMs is the first test I would run.

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answered 2015-03-04 16:16:54 -0600

sripriya gravatar image

Check the security group rules you have enabled for the two VMs. You should have ICMP, TCP enabled for ping/iperf to work on each of these VMs

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Security Groups dont matter if the VMs are part of the same tenant. All VMs get default security group applied unless otherwise specified.

sfcloudman gravatar imagesfcloudman ( 2015-03-04 20:04:57 -0600 )edit

Th default security group in OpenStack needs to be modified to add egress and ingress TCP, UDP and ICMP traffic rules explicitly. The default any to any rule does not work for TCP, UDP and ICMP traffic.

sripriya gravatar imagesripriya ( 2015-03-04 22:43:41 -0600 )edit

Not true. This is only true if using floating IPS. If 2 instances are on the same l2 then all traffic between those instances is allowed by default SG.

sfcloudman gravatar imagesfcloudman ( 2015-03-04 23:11:24 -0600 )edit

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Asked: 2015-03-04 03:45:48 -0600

Seen: 580 times

Last updated: Mar 04 '15