AP9641 intermittently loses connection to cisco catalyst 9300 switch

[jackson3]

I have several sites with new APC SMT3000 UPS's that constantly lose connection to the network. The network card firmware is 2.2.1.1. This is constantly causing the monitoring system to send out emails and warnings. Dialing into the card there is nothing in the logs to show the card went down.

At the site, I could see the link light on the front of the switch go off, yet the link light on the card never did, so i am wondering if the switch is having an issue where it constantly has to re-establish a connection. I do not have this problem with the AP9361, I swapped my last on out with one of the troublesome UPS's and all problems went away.

I have replaced the card with another AP9641, moved to a different port on the switch, used 2 different brand new LAN cables, changed the port speed on the card from automatic to 100 and 10 full duplex, reset the switch ports to default, tried turning on and off POE, still having the same problem.

I have two SMT1500 UPS's on the network not having any issues with the AP9641, same set up except the firmware on the cards is 1.3.3.1. They are not experiencing any problems. All UPS's have the same ID18 9.8 firmware in them.

One final thing, if I start a continuous ping from my laptop to the network card, it never loses connection, even over several hours, yet as soon as i stop the ping the intermittent communication loss starts.

Any suggestions?

Thanks

[JonPro]

Hi @jackson3 

Thank you for reaching out to the SE Community, my name is Jon and I will assist you with this query.  I am sorry to hear about the issue that you are experiencing with the AP9641.

If you go to About > Network and check the Uptime, this is one way for you to confirm if it really loses communication.  We recommend applying the latest NMC3 firmware to resolve the problem.

Please download and apply the firmware v2.3.1.1 below to the NMC3s that you have.

SFNMC3SU231 - UPS Network Management Card 3 Firmware v2.3.1 for Smart-UPS with AP9640/41/43