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I have got three Ubuntu servers (virtual) running in cloud, they all are sitting in the same virtual LAN and configured with similar specs. However when I run tracepath on those three hosts to a specific target host, one of them comes out with strange output saying too many hops whereas the other two can can reach the target with 2 hops.

In fact it should be the same number of hops on all of them, any ideas what could be the issue here? Does the network stack needs a restart?

Working:

root@xx-yy-zz-02:~# tracepath target.mail.com
 1?: [LOCALHOST]                                         pmtu 1500
 1:  192.168.32.2                                           1.797ms
 1:  192.168.32.2                                           1.694ms
 2:  target.mail.com                                     3.075ms reached
     Resume: pmtu 1500 hops 2 back 2

Not working:

root@xx-yy-zz-01:/var/log# tracepath target.mail.com
 1?: [LOCALHOST]                                         pmtu 1500
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     Too many hops: pmtu 1500
     Resume: pmtu 1500

Routing configuration looks same on both the hosts, network team points at the virtual server itself.

muru
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DevM
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    I'd wager on a bug in tracepath. Use "mtr" instead: http://manpages.ubuntu.com/manpages/zesty/man8/mtr.8.html – Rinzwind Apr 18 '17 at 11:21
  • Thanks Rinzwind, I will give it a try and let you know. We also had mail timeout issues on the same virtual host where the mail times out after 5 minutes . – DevM Apr 18 '17 at 12:11
  • mtr seems to have the same thing but definitely better tool. I have tried running tracepath with different packet size and it seems to get no response from the next hop when the packet size is 1460. – DevM Apr 19 '17 at 02:32

0 Answers0