On Tuesday morning I'm going to switch the OpenStack Keystone token engine from UUID tokens to fernet tokens[0]. The changeover[1] will be abrupt and cause all existing sessions to reset (e.g. if you're using Horizon you'll have to log back in, and if you're in the middle of creating a VM that creation will probably fail.) Should you encounter this interruption, just try again in a few minutes and everything should be fine.
The new tokens will generally behave the same from a user standpoint, but will allow us to simplify and modernize things on our end a bit.
The switch will happen at 15:00 UTC on this Tuesday, 2020-02-18. That's 7AM, Pacific Coast time.
[0] https://docs.openstack.org/keystone/pike/admin/identity-fernet-token-faq.htm...
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