Its recently been reported that Citrix NetScaler VPX networking fails on hypervisors running VMware vSphere build 2143827. The symptoms include a complete failure of any networking in or out of a Citrix NetScaler appliance with multiple VPX firmware revisions affected.
There is currently no solution to the issue as of yet except running the NetScaler on a non patches vSphere host or rolling back the update by rebooting the ESXi host and hitting SHIFT-R during the booting process to revert ESXi to the previous patching level.
I will update this post as an when an official solution is released from either Citrix or VMware.
Ok so there is still no official fix from either VMware or Citrix but the below appears to work for about 90% of cases,
1/ Putty onto the NetScaler and then type ” shell” and enter.
2/ navigate to /flash/boot/defaults
3/ edit the loader.conf
4/ add the following to the bottom of the config file add “hw.em.txd=512”
5/ save the change and exit the config file, reboot the vpx and test.
This should resolve most cases of the problem although I have seen mentions that this does not work for some. I believe Citrix are working on a fix which hopefully will cover a decent range of major revisions as a lot of customers are still utilising 10.0,10.1.
Author: Dale Scriven