Installation guide

Function Components Description
gnbd_serv A server daemon that allows a node
to export local storage over the
network.
LVS pulse This is the controlling process which
starts all other daemons related to
LVS routers. At boot time, the
daemon is started by the
/etc/rc.d/init.d/pulse script. It
then reads the configuration file
/etc/sysconfig/ha/lvs.cf. On the
active LVS router, pulse starts the
LVS daemon. On the backup router,
pulse determines the health of the
active router by executing a simple
heartbeat at a user-configurable
interval. If the active LVS router fails
to respond after a user-configurable
interval, it initiates failover. During
failover, pulse on the backup LVS
router instructs the pulse daemon on
the active LVS router to shut down all
LVS services, starts the send_arp
program to reassign the floating IP
addresses to the backup LVS router's
MAC address, and starts the lvs
daemon.
lvsd The lvs daemon runs on the active
LVS router once called by pulse. It
reads the configuration file
/etc/sysconfig/ha/lvs.cf, calls
the ipvsadm utility to build and
maintain the IPVS routing table, and
assigns a nanny process for each
configured LVS service. If nanny
reports a real server is down, lvs
instructs the ipvsadm utility to remove
the real server from the IPVS routing
table.
ipvsadm This service updates the IPVS routing
table in the kernel. The lvs daemon
sets up and administers LVS by
calling ipvsadm to add, change, or
delete entries in the IPVS routing
table.
Cluster Components
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