Red Hat GFS 6.0 -, Administrator'S Manual

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38 Chapter 6. Creating the Cluster Configuration System Files
6.2. CCS File Creation Tasks
To create the CCS files perform the following steps:
1. Create the
cluster.ccs
file.
2. Create the
fence.ccs
file.
3. Create the
nodes.ccs
file.
Note
The contents of CCS files are case sensitive.
6.3. Dual Power and Multipath FC Fencing Considerations
To ensure that fencing completely removes a node that has dual power supplies or multiple paths to
FC storage, both power supplies and all paths to FC storage for that node must be fenced.
To fence dual power supplies and multiple paths to FC storage, you need to consider the following
actions when creating the
fence.ccs
and
nodes.ccs
files:
• fence.ccs
— For each power supply and each path to FC storage define a fencing device
(
fence.ccs:fence_devices/ DeviceName
).
• nodes.ccs
— For each node with dual power supplies, include in the fencing method section
(
nodes.ccs:nodes/ NodeName /fence/ Methodname
) a fencing device for each power supply .
For each node having multiple paths to FC storage, include in the fencing method section a fencing
device for each path to FC storage.
GFS supports dual power-supply fencing with the APC MasterSwitch only; it supports
multipath FC fencing with Brocade and Vixel switches. For more information about creating
the
fence.ccs
and
nodes.ccs
files, refer to Section 6.6 Creating the
fence.ccs
File and
Section 6.7 Creating the
nodes.ccs
File . For more information about fencing, refer to
Chapter 10 Using the Fencing System .
6.4. GNBD Multipath Considerations for CCS Files
GNBD multipath allows you to configure multiple GNBD server nodes (nodes that export GNBDs to
GFS nodes) with redundant paths between the GNBD server nodes and storage devices. The GNBD
server nodes, in turn, present multiple storage paths to GFS nodes (GNBD clients) via redundant
GNBDs. With GNBD multipath, if a GNBD server node becomes unavailable, another GNBD server
node can provide GFS nodes with access to storage devices.
Make sure to take the following actions when setting up CCS files for GNBD multipath:
•
Configure a fencing method that physically removes each GNBD server node from the network.