On Thu, Aug 7, 2025 at 11:28 AM W. Michael Petullo <[email protected]> wrote:
> I would like to use Guacamole 1.6.0 to connect using RDP to a pool of > hosts behind a round-robin DNS A record. When I try to connect to: > > rdp://USER:[email protected] > > the connection hangs with my browser displaying Guacamole's black screen > (the one that displays "Connected to Guacamole. Waiting for response..."). > Once this happens, I cannot interact with Guacamole because reloading > the client in my browser returns to the black screen. Continuing seems > to require a restart of guacd. > > I have not yet found why this is happening. It does not happen if I > select a host with a one-to-one A record (as opposed to round-robin). > My hunch is that guacd is making more that one connection, which likely > results in connections to two or more hosts and thus confusion. However, > I have not yet found any evidence of this. > > Can you check the guacd logs (syslog/journald) and see if there's anything logged during these connection attempts? If you don't see anything, maybe put guacd into debug mode and see if you get anything more useful? > Is there any expectation that Guacamole should work with round-robin DNS? > > I do not know of a particular reason why it wouldn't, but I haven't tried it. > Should there at least be a protection against an account becoming > unusable until guacd restarts? > > I don't think the account is unusable - you can likely still return to the Guacamole home screen and launch another connection, it's just causing something to go haywire with that specific connection until the guacd process is terminated. I'm sure you've already thought of this, but, rather than doing a DNS round-robin connection for RDP, you could throw a load balancer (HAProxy, for example) in front of the RDP servers and let it do the balancing. Or use Guacamole's built-in load balancing connection groups - at least until we figure out why it isn't working. -Nick
