HI,

last week I had an issue on my on-prem Horizon infrastructure:

Over the course of 2/3 days many agents  on Manual VDI Pools and RDSH hosts went into an unreachable state. 

Reboot did't help, the only way to re-establish the connectivity was an re-install.

Support couldn't really help, apart: yea some issue, re-install the agents.  I'm the only one with this issue? 

I suspect that the credentials between the connection servers and the agents where invalidated and the re-install recreates them, but I see nothing obvious in the logs.