Vyatta : Interfaces Become Unresponsive

Note When Vyatta Core got discontinued, a group of its users who wanted to keep using it forked the last available source code to start VyOS. See more here: https://vyos.io/

I recently deployed a Vyatta router into a Hyper-V test environment to connect multiple host-only networks and provide Internet access. The deployment was a success and is detailed here.

I found that after a large file transfer (download) or 3 or 4 days of use one or more of the interfaces on the Vyatta device would stop responding. Using tcpdump I found that the traffic siomply was not reaching the interface(s) that had stopped working: sudo tcpdump -nvi eth1

Intially I wondered if the VM was running low on memory; I had assigned only 128MB of RAM, so increased this to 256MB only to expereicne the same issues a few days later. I then came across trhe following forum post http://www.vyatta.org/forum/viewtopic.php?t=6221&sid=a15464ed60549a515c43bca4c26909b7¬†which described my issue perectly. The solution? Configure the VM to have 2 vCPU’s – ever since the Vyatta virtual router has been stable.