Hi @Cuong Le Van ,
It is necessary to run the PSConfig command or run SharePoint Configuration Wizard on the all SharePoint servers after installing CU.
Additionally, it must be running on the server which is hosting “Central Administration” site first and then on the WFE and APP servers. It’s a 6-step process which might take an hour at the max (in an ideal scenario) to run and complete. Once it’s completed successfully on the server where CA is hosted, please try opening the CA site and make sure everything looks fine and make sure you’re able to access the SharePoint sites. By any chance if the CA site is not coming up, please stop right there and fix it. Without fixing the CA site issue, please don’t proceed further with running the Configuration wizard on the other servers. This is the basic thumb rule to be followed while patching a SharePoint farm.
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