On 04/11/13 11:18, David Teigland wrote: > On Mon, Nov 04, 2013 at 09:31:08AM -0500, Digimer wrote: >>>>> We are having a node two cluster with manual fencing configuration . >>>> >>>> An HA cluster with manual fencing is no cluster at all. >>> >>> No. It is a cluster. But it provides no high availability. >> >> Let me echo Zama and Michael. >> >> Clusters without real fencing are not supported. Manual fencing was >> dropped because it's not reliable and it is way too easy for mistakes to >> happen. >> >> Please add real fencing. Test it to make sure it works. I expect >> things will start working fine then and you will have no trouble joining >> a node back to your cluster. > > The dogmatic attitude against manual fencing is disturbing. It is a > perfectly legitimate and useful way to run a cluster as long as it's used > appropriately and with an understanding of how it works, the limitations > and tradeoffs. > > Dave https://access.redhat.com/site/articles/28601 === Fence Agent RHEL 5 RHEL 6 manual no [3] no === [3] - fence_manual is shipped in Red Hat Enterprise Linux 4 and Red Hat Enterprise Linux 5, but it is not supported. See RHEL High Availability: Manual Fencing (fence_manual vs. fence_ack_manual) for details on fence_manual vs. fence_ack_manual. That links to: https://access.redhat.com/site/node/36302 === Usage of the fence agent fence_manual implies that every time a node fails in your cluster, it will always require manual intervention to continue cluster operations, including the ability to relocate a failed service to a functional node. This is the reason that fence_manual is unsupported since it does not provide for high availability unless you have a system administrator monitoring your cluster 24 hours a day. In addition, it can cause corruption of cluster resources if used incorrectly. === This seems like a very good reason to have a "dogmatic" opposition to manual fencing. Red Hat doesn't support it and mis-use can cause data corruption and loss. Given how poorly most people understand fencing's role, it's just asking for trouble. So I stand by my (very strong) recommendation against manual fencing. -- Digimer Papers and Projects: https://alteeve.ca/w/ What if the cure for cancer is trapped in the mind of a person without access to education? -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
