1PULSE(8) System Manager's Manual PULSE(8)
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6 pulse - heartbeating daemon for monitoring the health of cluster nodes
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9 pulse [-c file|--configfile= file] [-n|--nodaemon]
10 [--forceactive] [--lvs= path] [--fos= path]
11 [-v|--verbose] [-t|--test-start] [--norun]
12 [-?|--help] [--usage] [--version]
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15 pulse is a daemon used by lvsd nodes to monitor one another's health
16 and to initiate the failover of the lvsd or fos daemon. It makes use
17 of the lvs.cf(5) configuration file for items such as length of time
18 between heartbeats and length of time before declaring the remote
19 server to be dead and initiate a failover.
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21 pulse, which runs on the primary and backup nodes, is used by each to
22 determine that the other is still alive. If the backup node fails to
23 receive a heartbeat from the primary node after a set amount of time
24 (specified in lvs.cf), it will assume ownership of all virtual ser‐
25 vice(s) being provided by the primary node. Its takeover process
26 includes bringing up aliased device(s) for all virtual service(s) as
27 well as sending out gratuitous ARPs to associate the floating IP(s)
28 with the MAC address of the backup node.
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30 If and when a failed primary node returns to a functioning status, it
31 assumes the backup role unless specifically forced to assume the pri‐
32 mary role. To reduce the number of faults seen by clients and avoid the
33 breaking persistent client connections, you should minimize the number
34 of failovers.
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37 -c file|--configfile= file
38 Normally, pulse uses lvs.cf as its configuration file, but this
39 can be overridden and another file can be used.
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41 -n|--nodaemon
42 Normally, pulse runs as a daemon but with this option runs in
43 the foreground. When running in this mode, pulse sends all out‐
44 put to STDOUT instead of to syslog.
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46 --forceactive
47 When this flag is used, the machine that pulse runs on will
48 forceably take over as the primary lvsd router and other machine
49 will become the backup.
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51 --lvs= path
52 By default, pulse looks in /usr/sbin for lvsd; use path to tell
53 pulse to look elsewhere for the program.
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55 --fos= path
56 By default, pulse looks in /usr/sbin for fos; use path to tell
57 pulse to look elsewhere for the program.
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59 -t|--test-start
60 Runs pulse in a test mode. Reports, but does not actually start,
61 the rest of the daemom processes (lvsd, fos, etc.).
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63 --norun
64 Historical. Same as --test-start.
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66 -v|--verbose
67 Displays debugging information
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69 -?|--help
70 Shows a verbose usage listing.
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72 --usage
73 Outputs a terse argument summary.
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75 --version
76 Displays program version.
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80 lvs.cf(5), ipvsadmn(8), lvsd(8). fos(8). nanny(8).
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84 Erik Troan <ewt@redhat.com>
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884th Berkeley Distribution Tue Sep 21 1999 PULSE(8)