By now you should know what to do if your STS certificate expire, but if you have been caught on this one here are simple steps to recover:
NOTE: In vCenter Server version 6.5U3k, 6.7 U3j, or 7.0 U1, you receive a weekly notification when the vCenter Single Sign-On Security Token Service (STS) signing certificate is close to expiration. Notifications start 90 days before the STS certificate expires and turn into daily over the last week before expiration.
If you not running versions mentioned above then you can check STS certificate manually:
- Download phyton script from VMware website or click here
- Open script in text editor
- SSH to VCSA
- Create new checksts.py file for example
vi checksts.py
- Copy script’s body to your checksts.py file
- Run
python checksts.py

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