15 years ago
The problem is now solved.
The problem was escalated to the network group, who looked into it and discovered that there was a WAN accelerator in the path that did not have VLAN tagging enabled on a connection to a trunk port.
I know generally what that means, but don't have a clear understanding of how that would have caused the odd phenomenon encountered here, in which the telnet session would connect, but the controller session would not connect until the telnet session connected.
However, enabling VLAN tagging was the only change made along the route between the devices, and the controller is now coming online the way it's supposed to.
Thanks to everyone for taking the time to give their thoughts on this problem.
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