11bb4785f8
Since kdump already support dump in cluster environment, this patch add a howto file to RPM package to describe how to configure kdump in cluster environment. Signed-off-by: arthur <zzou@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com>
67 lines
2.7 KiB
Plaintext
67 lines
2.7 KiB
Plaintext
Kdump-in-cluster-environment HOWTO
|
|
|
|
Introduction
|
|
|
|
Kdump is a kexec based crash dumping mechansim for Linux. This docuement
|
|
illustrate how to configure kdump in cluster environment to allow the kdump
|
|
crash recovery service complete without being preempted by traditional power
|
|
fencing methods.
|
|
|
|
Overview
|
|
|
|
Kexec/Kdump
|
|
|
|
Details about Kexec/Kdump are available in Kexec-Kdump-howto file and will not
|
|
be described here.
|
|
|
|
fence_kdump
|
|
|
|
fence_kdump is an I/O fencing agent to be used with the kdump crash recovery
|
|
service. When the fence_kdump agent is invoked, it will listen for a message
|
|
from the failed node that acknowledges that the failed node is executing the
|
|
kdump crash kernel. Note that fence_kdump is not a replacement for traditional
|
|
fencing methods. The fence_kdump agent can only detect that a node has entered
|
|
the kdump crash recovery service. This allows the kdump crash recovery service
|
|
complete without being preempted by traditional power fencing methods.
|
|
|
|
fence_kdump_send
|
|
|
|
fence_kdump_send is a utility used to send messages that acknowledge that the
|
|
node itself has entered the kdump crash recovery service. The fence_kdump_send
|
|
utility is typically run in the kdump kernel after a cluster node has
|
|
encountered a kernel panic. Once the cluster node has entered the kdump crash
|
|
recovery service, fence_kdump_send will periodically send messages to all
|
|
cluster nodes. When the fence_kdump agent receives a valid message from the
|
|
failed nodes, fencing is complete.
|
|
|
|
How to configure cluster environment:
|
|
|
|
If we want to use kdump in cluster environment, fence-agents-kdump should be
|
|
installed in every nodes in the cluster. You can achieve this via the following
|
|
command:
|
|
|
|
# yum install -y fence-agents-kdump
|
|
|
|
Next is to add kdump_fence to the cluster. Assuming that the cluster consists
|
|
of three nodes, they are node1, node2 and node3, and use Pacemaker to perform
|
|
resource management and pcs as cli configuration tool.
|
|
|
|
With pcs it is easy to add a stonith resource to the cluster. For example, add
|
|
a stonith resource named mykdumpfence with fence type of fence_kdump via the
|
|
following commands:
|
|
|
|
# pcs stonith create mykdumpfence fence_kdump \
|
|
pcmk_host_check=static-list pcmk_host_list="node1 node2 node3"
|
|
# pcs stonith update mykdumpfence pcmk_monitor_action=metadata --force
|
|
# pcs stonith update mykdumpfence pcmk_status_action=metadata --force
|
|
# pcs stonith update mykdumpfence pcmk_reboot_action=off --force
|
|
|
|
Then enable stonith
|
|
# pcs property set stonith-enabled=true
|
|
|
|
How to configure kdump:
|
|
|
|
Actually there is nothing special in configuration between normal kdump and
|
|
cluster environment kdump. So please refer to Kexec-Kdump-howto file for more
|
|
information.
|