robertanderson256
New member
I’ve been troubleshooting a strange issue with a GLC-TE module and I can’t quite pin down what’s causing it. The run is simple—short Cat6, under 60 meters, nothing unusual and most of the other copper links on the same switch behave perfectly. But this one keeps acting up in a way that doesn’t match any obvious pattern.
Sometimes it negotiates at 1G like it should, other times it drops to 100M, and occasionally it won’t negotiate at all unless I manually force the speed. Even after forcing it, the link will randomly flap every few minutes. I swapped patch leads, tested the in-wall cable, reseated everything, and even replaced the module. The strange part is that when I put the same GLC-TE into another switch, it works flawlessly.
So now I’m stuck wondering whether it’s something odd about that specific port, a hidden cable issue that the tester didn’t catch, or some interference on the path that only affects this link.
Has anyone else run into unpredictable link behavior with GLC-TE modules? What turned out to be the cause in your case?
Sometimes it negotiates at 1G like it should, other times it drops to 100M, and occasionally it won’t negotiate at all unless I manually force the speed. Even after forcing it, the link will randomly flap every few minutes. I swapped patch leads, tested the in-wall cable, reseated everything, and even replaced the module. The strange part is that when I put the same GLC-TE into another switch, it works flawlessly.
So now I’m stuck wondering whether it’s something odd about that specific port, a hidden cable issue that the tester didn’t catch, or some interference on the path that only affects this link.
Has anyone else run into unpredictable link behavior with GLC-TE modules? What turned out to be the cause in your case?