Image Sync Fails in Aria Automation: "User sessions count is limited to 150"

Products

• VMware vCenter Server
• VCF Operations/Automation (formerly VMware Aria Suite)

Issue/Introduction

• When performing image synchronization or processing Content Library items from Aria Automation (formerly vRealize Automation), the process fails with an error " Image synchronization failed when processing content library items. Cannot list libraries ( com.vmware.vdcs.vsphere-auth-lib.user_session_count_exceeded  User sessions count is limited to 150. Existing sessions count is 150 for user "
  
  
• In /var/log/vmware/content-library/cls.log, we observe error similar to below:

  at com. vmware. cis. SessionSyncApiInterface$CreateApiMethod. doInvoke (SessionSyncApiInterface. java: 39) [cls-vmodl-1.0.0. jar: ?]
  defaultMessage = User sessions count is limited to 150. Existing sessions count is 150 for user ####.####. com\#######.,
  at com. vmware. cis. SessionSyncApiInterface$CreateApiMethod. doInvoke (SessionSyncApiInterface. java: 39) [cls-vmodl-1.0.0. jar: ?]
  defaultMessage = User sessions count is limited to 150. Existing sessions count is 150 for user ####.####. com\#######.,
  at com. vmware. cis. SessionSyncApiInterface$CreateApiMethod. doInvoke (SessionSyncApiInterface. java: 39) [cls-vmodl-1.0.0.jar: ?]
  defaultMessage = User sessions count is limited to 150. Existing sessions count is 150 for user ####.####. com\#######.,
  at com. vmware. cis. SessionSyncApiInterface$CreateApiMethod. doInvoke (SessionSyncApiInterface. java: 39) [cls-vmodl-1.0.0. jar: ?]
  defaultMessage = User sessions count is limited to 150. Existing sessions count is 150 for user ####.####. com\#######.,
  at com. vmware. cis. SessionSyncApiInterface$CreateApiMethod. doInvoke (SessionSyncApiInterface. java: 39) [cls-vmodl-1.0.0. jar: ?]
  defaultMessage = User sessions count is limited to 150. Existing sessions count is 150 for user ####.####. com\#######.,
  

Environment

• VMware vCenter Server
• VMware Aria Automation

Cause

• The issue occurs because the number of concurrent active sessions for a single user in the vSphere UI/API layer has reached its hard-coded or configured limit (defaulting to 150 in certain versions/configurations).
• When Aria Automation or other integration services make frequent calls to the Content Library service, the session pool is exhausted, preventing new synchronization tasks from starting.

Resolution

     To resolve this issue, you must increase the maximum allowed active SSO Sessions within the vSphere UI configuration.

1. Log in to the vCenter Server Appliance (VCSA) via SSH as the root user.  
   
   
2. Navigate to the below directory :

   cd /etc/vmware/vsphere-ui/

3. Create a backup of the webclient.properties file: 

   cp webclient.properties  webclient.properties.bak

4. Open the file for editing using vi: 

    vi /etc/vmware/vsphere-ui/webclient.properties 

5. Navigate to the end of the file and add the following configuration line: 

   sso.active.sessions.max = 1000

6. Save and close the file 

   Esc :wq!

7. Restart the vSphere UI service for the changes to take effect: 

   service-control --restart vsphere-ui

   
   Note: Once the service has restarted, the new limit of 1000 sessions will be active, and image synchronization failures related to session exhaustion should be resolved.