With the recent deprivation of SHA1 certificates in favour of the more secure SHA2 it’s important to know that SCOM uses SHA1 to manage workloads for cross platform monitoring (Unix / Linux).
Have no fear the MS SCOM team have released an article on how to replace your existsing SHA-1 certificates with the newer SHA256 certificates.
It is important to note that you will need to update your 2012 R2 environments to UR 12 and your 2016 environments to UR2 respectivly in order to use the new SHA256 certificates by default.
The article is available here