Anyone ever get an issue where an upgraded uag fails to work. I'm going from 3.7 to 2009 on 3 different ones right now. 2 work fine and 1 is failing. Checking the f5 monitor it returning a 403 error for some reason, even though if I go to the uag directly I don't see a 403. The esmanger log show "Sending bad request. Incoming request does not have valid host header: null, XFH: null" so something is wrong, I compare the log with working one and that entry isn't there. 3.7 doesn't seem to trigger that since if I turn the old appliance on it works fine, but 2009 is having issues with the f5, just with this one f5 pool. I have 3 different f5 pools, all with 2 uags each, and its only one of these that isn't working. I'm assuming its on the f5 side, but can't seem to find it.
did you ever find a fix for this?
You may need to update your F5 iApp. https://support.f5.com/csp/article/K15041
Also you want to review the F5 documentation on load balancing UAGs in F5.
https://www.f5.com/pdf/solution-center/load-balancing-vmware-unified-access-gateway-servers-deployme...
At the top of page 23 in that PDF, related to OneConnect is what helped us. We change to not using OneConnect and it resolved our issue. It is related to newer UAGs not allowing multiplexing from F5.
Hope this helps.
It wasn't one connect, but I'm pretty the updated f5 instructions fixed it. Think there was a host variable in the monitor that wasn't in the older ones.