Cpk | C&CZ News

CPK messages are initially sent to the CPK mailing list, you can (un)subscribe via this link. You can also follow the service interruption messages via RSS using the link in the title under the RSS icon. If the CPK takes more time to resolve, any updates are published on this website.

For RU wide service interruption see meldingen.ru.nl.

Service Interruptions

1407: NFS problems under investigation

When we moved the gateways of our networks from the old location to the new firewalls, we have received some complaints about NFS filesystems having slowness, longer delays or unavailability. In general NFS should never be a requirement for a clusternode job if you can avoid it, because this I/O is always much slower than local I/O from /scratch. We are investigating how we can optimise the network to resolve this issue, but we are hard pressed to know the exact cause of the problem....

1415: Clusternode maintenance day - February 6th 2026

Every half year we do clusternode maintenance, with at least a package ugprade and a reboot, but sometimes other maintenance can happen, such as changes in filesystems or network configurations. The upcoming date for this maintenance is February 6th, 2026 (Friday)

Resolved Reports

1356: Network problems after maintenance on the RU core router

After maintenance on the central routers, our servers on the 25Gbit network couldn’t send traffic to the internet. The cause or nature of the problem appears to be in the central RU routing. By resetting the interface to our network, RU Connectivity can fix this, when it occurs again. RU Connectivity contacted their maintenance provider to investigate this problem. Final solution: After a few failed attempts, it was possible to define a static route in the central routers to our networks....

1355: Jupyterhub restarted

Some users were unable to login, the server had become unstable, which made a reboot necessary. Unfortunately, the jupyterhub service still needs a manual startup, which didn’t happen until 13:24 hours. The service is now working again. We are working to fix the reboot problem.

1354: DHCP server down due to config error

A typo that could propagate to shutdown the DHCP server had the effect that some network devices did not get an IP address when they were switched on and that others, whose address lease expired in this period, lost their IP address and thus their access to the network.. We’ll improve the process to prevent a typo from bringing down the DHCP server in the future.

1353: Jupyterhub22 refused to start this morning

After a scheduled reboot of the machine running jupyterhub, jupyter failed to start properly. The service started after invoking a manual start command. The measures taken to resolve this recurring problem have not proven to be sufficient.

1352: DNS broken for z.science.ru.nl

Due to a misconfiguration of the DNS in the z.science.ru.nl zone, all shares were not available during the outage. Extra tests are added to prevent a future occurrence.

1351: All Science services down 15 minutes Thursday Oct 19 07:00-07:15 due to router reboot

The router for most Science services urgently needs a reboot. This has been scheduled for early morning. In the unlikely case that this reboot fails, ILS Connectivity is on campus to fix it.

1350: Mailman not accepting messages

In preparation of the migration to Microsoft Exchange Online Protection (MS EOP), we added another mail exchange server (mx5) to be addressed directly by MS EOP. However, having had mx4 in production for some time, we forgot to test mx5 in conjunction with our mailman server (zaaivm). This could result in a bounced mail ’not accepting messages’ for FNWI users (employees and students) using @ru.nl addresses. Meanwhile, mx5 has been made known to zaaivm thus resolving this issue....

1349: Jupyterhub22 refused to start this morning

After a scheduled reboot of the machine running jupyterhub, jupyter failed to start properly. The service started after invoking a manual start command.

1348: Roundcube problem

After an upgrade of Roundcube it was temporarily not possible to send e-mails. After a small change in the configuration file the problem was resolved.

1347: Poster printer kamerbreed broken

The poster printer kamerbreed was broken. It couldn’t be fixed, so we ordered a new HP Designjet Z6 44 inch postscript. The ordering and delivery took way too long, the new poster printer was in operation on November 13. The new printer is twice as fast, so the speed of service will be even better. When our poster printer breaks down, users that need posters can go to Radboud Post&Print.