This is a workaround, Citrix is actively working on this problem, You can follow any updates on this issue through the ID number # 0510673.
The following are the workarounds for this issue:
Install NetScaler VPX appliance on a previously known good VMware version and build.
- SSH and log on to Citrix NetScaler VPX appliance as nsroot.
- Type shell.
- Change directory (cd) to /flash/boot.
- Create file /flash/boot/loader.conf.local (if not present) with same permissions as /flash/boot/loader.conf. Add the following line and reboot: hw.em.txd = 512
- To create the file, use command touch loader.conf.local.
NetScaler VPX network connectivity issue on VMware ESXi 5.1.0 build 2191751 and VMware ESXi 5.5 build 2143827 is caused by “tx_ring_length” mismatch, which causes TX stalls.