If you are seeing the neighbor table overflow message in the dmesg log it means that the ARP cache of your server has run out of space. This can happen if you host multiple cloud servers and or massively scale Kubernetes, Proxmox or other virtualization solutions on one physical server, as every VM / Pod / … Read more
If you are using CloudStack or OpenStack the default behaviour of live migration is configured as launch & pray it will complete. This can cause – and in practice probably will cause – VMs which have a lot of dirty pages to not complete live-migration at all. [section background_repeat=”repeat” background_position=”center top” background_attachment=”static” background_scroll=”none”] This is … Read more
The version 4.0.4 of dlm (Distributed Locking Manager) currently shipped with Ubuntu 16.04 LTS has a severe bug that causes fencing of a remote host initiated by other clustered components to fail. This can cause an entire cluster to be stuck waiting and/or all cluster nodes disconnecting from the cluster for no reason. This fencing … Read more