Firmware upgrade on datacenter core switches. Few short breaks will happen. In most cases spanning tree will take care of traffic rerouting so breaks will be short.
Update at 21:16: Some Ukko nodes failed to switch network traffic to another network interface card (NIC) and thus network connections to those nodes were interrupted for appoximately 3 minutes during reboots of the switch via which the traffic to blade chassis those Ukko nodes were attached to was configured to flow. NIC bonding configurations will be fixed so that this kind of unneccessary breaks can be avoided.
Update at 21:29: The break is over.
Update at 2012-08-13 21:18: Ukko cluster's network switches are now configured to drop host port (access port) immediately if uplink port goes down. This will fix the forementioned problem when hosts' NIC bonding configuration didn't notice the loss of uplink.
Last updated on 13 Aug 2012 by Pekka Tonteri - Page created on 7 Aug 2012 by Pekka Tonteri