Hello Dominik,

If VM_DST is the source of ARP (as per your tcpdump), you should see those
requests in tcpdump of eth0 interface in VM_DST, which we are not. Then are
you saying that VM_DST didn't send those requests? Or is there something 
wrong with your terminology? 

Also, at what stage in the lifetime of the VM did you observe this problem 
i.e.: 
just after the VM has booted up or after everything has stabilized (say, the VM
has already got IP addresses) etc.:

Thanks,
Anand

________________________________________
From: Users <[email protected]> on behalf of Dominik 
Mostowiec <[email protected]>
Sent: Friday, October 23, 2015 7:30 PM
To: [email protected]
Subject: [Users] ARP response on wrong VM

Hi,
We have strange observations about ARP.
2 VMs on separated compute nodes.
VM_SRC: 10.189.85.11(02:86:45:5e:06:38), VM_DST: 10.189.85.10(02:25:6b:67:72:e9)

tcpdump on VM_SRC:
tcpdump -i eth0 -e arp
13:41:41.694854 02:25:6b:67:72:e9 (oui Unknown) > 02:86:45:5e:06:38
(oui Unknown), ethertype ARP (0x0806), length 42: Request who-has
10.189.85.11 tell 10.189.85.10, length 28
13:41:42.696888 02:25:6b:67:72:e9 (oui Unknown) > 02:86:45:5e:06:38
(oui Unknown), ethertype ARP (0x0806), length 42: Request who-has
10.189.85.11 tell 10.189.85.10, length 28
13:41:43.698889 02:25:6b:67:72:e9 (oui Unknown) > 02:86:45:5e:06:38
(oui Unknown), ethertype ARP (0x0806), length 42: Request who-has
10.189.85.11 tell 10.189.85.10, length 28
13:41:45.690163 02:25:6b:67:72:e9 (oui Unknown) > Broadcast, ethertype
ARP (0x0806), length 42: Request who-has 10.189.85.11 tell
10.189.85.10, length 28
13:41:45.690203 02:86:45:5e:06:38 (oui Unknown) > 02:25:6b:67:72:e9
(oui Unknown), ethertype ARP (0x0806), length 42: Reply 10.189.85.11
is-at 02:86:45:5e:06:38 (oui Unknown), length 28

3 x request to mack  02:86:45:5e:06:38 who-has 10.189.85.11 and no response.
And after that 1 request to all "who-has 10.189.85.11" and proper response.

On VM_DST:
tcpdump -i eth0 -e arp
13:41:41.886815 02:86:45:5e:06:38 (oui Unknown) > 02:25:6b:67:72:e9
(oui Unknown), ethertype ARP (0x0806), length 42: Reply 10.189.85.11
is-at 02:86:45:5e:06:38 (oui Unknown), length 28
13:41:42.888807 02:86:45:5e:06:38 (oui Unknown) > 02:25:6b:67:72:e9
(oui Unknown), ethertype ARP (0x0806), length 42: Reply 10.189.85.11
is-at 02:86:45:5e:06:38 (oui Unknown), length 28
13:41:43.890797 02:86:45:5e:06:38 (oui Unknown) > 02:25:6b:67:72:e9
(oui Unknown), ethertype ARP (0x0806), length 42: Reply 10.189.85.11
is-at 02:86:45:5e:06:38 (oui Unknown), length 28

3x response on previous 3 requests.
There is no request, only responses.
If vrouter send the response of request 'who-has 10.189.85.11' - the
response is on wrong VM.
If VM_DST OS should send this - on OS we don't see any request.

I think the response is send to wrong VM.

Could You look on this and help us to solve or explain it?

--
Regards
Dominik

_______________________________________________
Users mailing list
[email protected]
http://lists.opencontrail.org/mailman/listinfo/users_lists.opencontrail.org

_______________________________________________
Users mailing list
[email protected]
http://lists.opencontrail.org/mailman/listinfo/users_lists.opencontrail.org

Reply via email to