What is Stale Session?
A stale session used to mean that the session table in the router was either full or corrupt, such that you suddenly lost connectivity in practice, while the router was still claiming that you were connected. The main symptom was a total loss of usable connection; it could never be partial. These certainly still occur.
Resolution
The security appliance allows a maximum of five concurrent Adaptive Security Device Manager (ASDM) instances per context, if available, with a maximum of 32 ASDM instances between all contexts. If the number of concurrent sessions reaches five, ASDM denies any new connection attempts.
Issue the show asdm sessions command to display a list of active ASDM sessions and their associated session IDs. Issue the asdm disconnect command to terminate a specific session.
When you terminate an ASDM session, any remaining active ASDM sessions keep their associated session ID. For example, if there are three active ASDM sessions with the session IDs of 0, 1, and 2, and you terminate session 1, the remaining active ASDM sessions keep the session IDs 0 and 2. The next new ASDM session in this example would be assigned a session ID of 1, and any new sessions after that would begin with the session ID 3.
This example terminates an ASDM session with a session ID of 0. The show asdm sessions command displays the active ASDM sessions before and after the asdm disconnect command is issued, as shown:
hostname# show asdm sessions
0 192.168.1.1
1 192.168.1.2
hostname# asdm disconnect 0
hostname# show asdm sessions
1 192.168.1.2
