So in our environment we have two locations with a 9300x-24Y switch stack acting as Layer 3 core (2 switches per stack), and both units have had connection issues with both the Copper GLC-TE and GLC-SX-MMD modules (both Gig Modules). The GLC-SX-MMD are fiber links to other 9300 Layer 2 switches, and the copper GLC-TE are links to our Fortinet Firewalls. We ran into the issues at both Installation and again 8-10 months later when we executed our yearly network gear reboot. We also have the SFP-10G-SR modules as well and have never had an issue with devices using this SFP.
On the GLC-SX-MMD the issue is that the ports on the 9300x goes into err-disabled, and the fix has been to either shutdown and the no shutdown the effected port. If that doesn't work the fix has been to pull out and reseat GLC-SX-MMD and then plug the fiber back in. We have seen the issue on a 1m fiber patch cable that goes from the Layer 3 to our ISR Router as well so it isn't a fiber quality issue.
The GLC-TE the switch shows good connection on all ports at a-full a-1000 for connectivity, however when pinging the firewall IPs we drop 50-70% of the pings to the firewalls. To fix it both times we have had to pull the GLC-TE and reseat them in the port, and we have also had to reboot the firewall after that the connectivity is restored. (these are 3ft CAT 6 cables)
Code is 17.05.01 (Bengaluru)
I will be opening a case with our 3rd party vendor to review, but wanted to see if anyone else has reported issues with Gig Modules on the newer 9300x-24Y switches.
