Symptom

In Cisco DNA Center, devices may take a long time to resync and eventually fall into an "Device Unresponsive" error state, despite device being reachable via ICMP and SSH. When connecting to the switch via SSH, the banner prompt shows this. $ ssh username@switch Banner message!switch# Cisco DNA Center logs this error in the inventory logs: 2023-08-03 10:34:36,345 | ERROR | XDE ThreadPool 10 | | com.cisco.xmp.inventory | Exception Stack: com.cisco.nm.pal.client.PALException: 856882HANDLER_ERROR3.4.23[wired_host_iosxe_reader]Version.xpa/getVersion/getVersion.par@Rule0/HandlerChain/Handler2Failed to match expected device output due to expect timeout, current expect timeout 300000ms, expect time 300000ms, minimal matching length 0. Current output : switch# Current expects : Banner message!switch#\s*\z (Prompt) ERROR_TIMEOUT

Conditions

This was observed in Cisco DNA Center 2.3.3.x.

Workaround

To workaround this issue re-configure a banner with extra new lines to avoid the banner prompt and switch prompt from concatenating.

Further Problem Description