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This web page is no longer maintained. Information presented here exists only to avoid breaking historical links.
The Project stays maintained, and lives on: see the Linux-HA Reference Documentation.
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1 February 2010 Hearbeat 3.0.2 released see the Release Notes

18 January 2009 Pacemaker 1.0.7 released see the Release Notes

16 November 2009 LINBIT new Heartbeat Steward see the Announcement

Last site update:
2017-12-17 15:37:19

An Active/Active Two IP address Configuration

A common configuration is that of a high-availability server which simply provides two IP addresses (, and to be failed over between the nodes of our cluster. We will set this up as an active/active configuration.

/etc/ha.d/ file

logfacility daemon         # Log to syslog as facility "daemon"
node paul silas            # List our cluster members
keepalive 1                # Send one heartbeat each second
deadtime 10                # Declare nodes dead after 10 seconds
bcast eth0 eth1            # Broadcast heartbeats on eth0 and eth1 interfaces
ping             # Ping our router to monitor ethernet connectivity
auto_failback yes          # Try and keep resources on their "preferred" hosts
respawn hacluster /usr/lib/heartbeat/ipfail  # Failover on network failures

See the ipfail page for more information on ipfail.

/etc/ha.d/haresources file


The first word (paul or silas) on the line represents the "preferred" host for the service. The remainder of the line is the list of resources (services) which are part of this ResourceGroup. In this case, each ResourceGroup consists of only one resource -- an IP address. is a shorthand notation for IPaddr::, and is a similar shorthand for IPaddr::

Because auto_failback was enabled, when paul joins the cluster it will regain the address. Similarly, when silas joins the cluster, it will regain its ( service address. If an active/passive configuration is desired, then simply change auto_failback to no.

/etc/ha.d/authkeys file

/etc/ha.d/authkeys must be mode 600. See the section on GeneratingAuthkeysAutomatically for information how to generate good keys automatically.

auth 1
1 sha1 PutYourSuperSecretKeyHere

See Also, haresources, authkeys, AddressFailover, GettingStarted/OneIPAddress, An Active/Active Two IP address Configuration for version 2