Some weeks ago, I wrote a blog post about some strange SD-WAN 9.3.2 behaviour – see NetScaler SD-WAN 9.3.2 Bug. In the meantime. we got some new information.
First of all, it’s not possible to replay the found issues with virtual environments. So it may depend on hardware appliances or at least the fail-to-wire interfaces … dunno.
Next, Citrix released SD-WAN firmware 9.3.3.21 and a look into the release notes showed the following:
Issue ID 697906: NetScaler SD-WAN service is disabled when MPLS QOS queues with all tagged queues are configured through a WAN Link Template, and on receiving a packet without DSCP tag.
SD-WAN 9.3.21 Release Notes
Really? That sounds quite similar to the issues we stumbled upon. Anyway, we’re going to update the SD-WAN environment in question and test again. I’ll keep you informed!