Issue with checks for CLARIN-LT

[dietervu]

The CLARIN-LT checks give an error that I cannot trace myself: the OAI endpoint seems to work correctly and the SSL certificate is valid.

OAI-PMH CRITICAL: HTTPSConnectionPool(host='clarin.vdu.lt', port=443): Max retries exceeded with url: /oai/request?verb=Identify (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x14fccff72978>: Failed to establish a new connection: [Errno -2] Name or service not known',​))

See https://monitoring.clarin.eu/monitoring/host/show?host=CLARIN-LT and https://monitoring.clarin.eu/monitoring/service/show?host=CLARIN-LT&service=ssl_cert%20clarin.vdu.lt

[alex00111111]

We tried to connect to the Host from the Server but Ping/dig/head/etc get any valid. Most time it can't establish a connection.
We tested it also with a local PC (form local University Network) and a Smartphone (from EduRoam). The PC couldn't connect either, but from the smartphone it worked.

It looks like an DNS Issue, to solve it we must change the Name-Server of the monitoring-VM.

[alex00111111]

We have tried to change the NameServer, but on reboot it was overwritten.

[dietervu]

There used to be DNS (and/or firewall) problems with this host, after discussing it with Andrius, I thought it was solved. I setup a statuscake probe, and for most areas the access seems to be working well now since a couple of weeks, but in the logs I still notice problems with access from Warsaw (Poland). Including @uandrius to this issue so that he can comment

[WillemElbers]

We received a user report as well that (some?) handles are not resolving: http://hdl.handle.net/20.500.11821/11 and emails to the clarin.vdu.lt domain are not arriving (Your message couldn't be delivered. The Domain Name System (DNS) reported that the recipient's domain does not exist.)