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dlm_controld(8) [centos man page]

DLM_CONTROLD(8) 							dlm							   DLM_CONTROLD(8)

NAME
dlm_controld - dlm cluster control daemon SYNOPSIS
dlm_controld [OPTIONS] DESCRIPTION
The kernel dlm requires a user daemon to manage lockspace membership. dlm_controld manages lockspace membership using corosync cpg groups, and translates membership changes into dlm kernel recovery events. dlm_controld also manages posix locks for cluster file systems using the dlm. OPTIONS
Command line options override a corresponding setting in dlm.conf(5). For default settings, see dlm_controld -h. --daemon_debug | -D enable debugging to stderr and don't fork --foreground don't fork --log_debug | -K enable kernel dlm debugging messages --protocol | -r str dlm kernel lowcomms protocol: tcp, sctp, detect --debug_logfile | -L write debugging to log file --enable_plock | -p 0|1 enable/disable posix lock support for cluster fs --plock_debug | -P enable plock debugging --plock_rate_limit | -l int limit rate of plock operations (0 for none) --plock_ownership | -o 0|1 enable/disable plock ownership --drop_resources_time | -t int plock ownership drop resources time (milliseconds) --drop_resources_count | -c int plock ownership drop resources count --drop_resources_age | -a int plock ownership drop resources age (milliseconds) --post_join_delay | -j int seconds to delay fencing after cluster join --enable_fencing | -f 0|1 enable/disable fencing --enable_concurrent_fencing 0|1 enable/disable concurrent fencing --enable_startup_fencing | -s 0|1 enable/disable startup fencing --enable_quorum_fencing | -q 0|1 enable/disable quorum requirement for fencing --enable_quorum_lockspace 0|1 enable/disable quorum requirement for lockspace operations --fence_all str fence all nodes with this agent --unfence_all enable unfencing self with fence_all agent --help | -h print this help, then exit --version | -V Print program version information, then exit SEE ALSO
dlm_tool(8), dlm.conf(5) dlm 2012-04-05 DLM_CONTROLD(8)

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FENCE_NODE(8)							      cluster							     FENCE_NODE(8)

NAME
fence_node - a utility to run fence agents SYNOPSIS
fence_node [OPTIONS] nodename DESCRIPTION
This utility runs a fence agent against nodename. The agent and args are taken from the running cluster configuration based on clus- ter.conf(5). fence_node is a wrapper around the libfence functions: fence_node() and unfence_node(). These libfence functions use libccs to read the node fencing configuration, which means that corosync (with cman and ccs) must be running to use fence_node(8). The fenced(8) daemon is the main user of libfence:fence_node(), and the configuration details for that function are given in the fenced(8) man page. Fencing vs. Unfencing The main use for unfencing is with storage/SAN (non-power) agents. When using power-based fencing agents, the fencing action itself is supposed to turn a node back on after first turning the power off (this happens automatically with a "reboot" action, and needs to be configured explicitly as "off" + "on" otherwise.) When using storage-based fencing agents, the fencing action is not allowed to re-enable a node after disabling it. Re-enabling a fenced node is only safe once the node has been rebooted. A natural way to re-enable a fenced node's access to storage, is for that node to re- enable the access itself during its startup process. The cman init script calls fence_node -U (nodename defaults to local nodename when unfencing). Unfencing a node without an <unfence> configuration (see below) is a no-op. The basic differences between fencing and unfencing: Fencing 1. libfence: fence_node(), command line: fence_node nodename 2. Turns off or disables a node. 3. Agents run with the default action of "off", "disable" or "reboot". 4. Performed by a cluster node against another node that fails (by the fenced daemon). Unfencing 1. libfence: unfence_node(), command line: fence_node -U nodename 2. Turns on or enables a node. 3. Agents run with the explicit action of "on" or "enable". 4. Performed by a cluster node "against" itself during startup (by the cman init script). OPTIONS
-U Unfence the node, default local node name. -v Show fence agent results, -vv to also show agent args. -h Print a help message describing available options, then exit. -V Print program version information, then exit. FILES
The Unfencing/unfence_node() configuration is very similar to the Fencing/fence_node() configuration shown in fenced(8). Unfencing is only performed for a node with an <unfence> section: <clusternode name="node1" nodeid="1"> <fence> </fence> <unfence> </unfence> </clusternode> The <unfence> section does not contain <method> sections like the <fence> section does. It contains <device> references directly, which mirror the corresponding device sections for <fence>, with the notable addition of the explicit action of "on" or "enable". The same <fencedevice> is referenced by both fence and unfence <device> lines, and the same per-node args should be repeated. <clusternode name="node1" nodeid="1"> <fence> <method name="1"> <device name="myswitch" foo="x"/> </method> </fence> <unfence> <device name="myswitch" foo="x" action="on"/> </unfence> </clusternode> SEE ALSO
fenced(8) cluster 2009-12-21 FENCE_NODE(8)

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