So I found solution by myself. I turned off corrupted host, then on pool master I forgot corrupted host (xe host-forget uuid=aaaaaaaaa-bbbb-cccc-ddddddddddd). Perform a clean install of corrupted host, setup everything as it was, then patch host with XOA. As last step I connect it back to the pool, now everything is working fine again. To be honest, I do not know what happened, but everything is working now.

It doesn't work like Citrix patches. Xen Orchestra will send a XAPI command to the host, that will in fact do a yum update command. The result is returned to XO and it will display available updates. We got a system using the best mirror for you: https://xcp-ng.org/docs/mirrors.html#original-mirror