Managing HP Serviceguard for Linux Ninth Edition, April 2009

Service Assistant Daemon: cmserviced...................................................................40
Quorum Server Daemon: qs....................................................................................41
Utility Daemon: cmlockd.........................................................................................41
Cluster SNMP Agent Daemon: cmsnmpd...............................................................41
Cluster WBEM Agent Daemon: cmwbemd.............................................................42
Proxy Daemon: cmproxyd.......................................................................................42
How the Cluster Manager Works ......................................................................................42
Configuration of the Cluster ........................................................................................42
Heartbeat Messages ......................................................................................................43
Manual Startup of Entire Cluster..................................................................................43
Automatic Cluster Startup ...........................................................................................44
Dynamic Cluster Re-formation ....................................................................................44
Cluster Quorum to Prevent Split-Brain Syndrome.......................................................44
Cluster Lock...................................................................................................................45
Use of a Lock LUN as the Cluster Lock........................................................................45
Use of the Quorum Server as a Cluster Lock................................................................46
No Cluster Lock ............................................................................................................48
What Happens when You Change the Quorum Configuration Online.......................48
How the Package Manager Works.....................................................................................49
Package Types...............................................................................................................49
Non-failover Packages.............................................................................................49
Failover Packages.....................................................................................................50
Configuring Failover Packages ..........................................................................50
Deciding When and Where to Run and Halt Failover Packages .......................51
Failover Packages’ Switching Behavior..............................................................51
Failover Policy....................................................................................................53
Automatic Rotating Standby..............................................................................54
Failback Policy....................................................................................................57
On Combining Failover and Failback Policies...................................................60
Using Older Package Configuration Files.....................................................................60
How Packages Run.............................................................................................................61
What Makes a Package Run?.........................................................................................61
Before the Control Script Starts.....................................................................................64
During Run Script Execution........................................................................................64
Normal and Abnormal Exits from the Run Script........................................................66
Service Startup with cmrunserv..................................................................................66
While Services are Running..........................................................................................67
When a Service or Subnet Fails, or a Dependency is Not Met......................................67
When a Package is Halted with a Command................................................................67
During Halt Script Execution........................................................................................68
Normal and Abnormal Exits from the Halt Script........................................................69
Package Control Script Error and Exit Conditions..................................................70
How the Network Manager Works ...................................................................................71
Stationary and Relocatable IP Addresses and Monitored Subnets...............................71
4 Table of Contents