Every now and then we find the following error in plack-api-error.log [ERROR] [OAuth2] Failed to warm up https://mpass-proxy.csc.fi/.well-known/openid-configuration: Can't connect: Name or service not known It does not seem to be related to a request to /api/v1/ as we cannot find any requests from around that timestamp. At this point I don't know what exactly executes the warming up process and why the DNS resolution fails when otherwise OIDC authentication works just fine. Is it related to Koha, our Koha server, the DNS server we are using or the OIDC target server? Anyway in case someone else is experiencing the same issue, I thought it'd be useful to create a Bug for this.