Installation guide

gnbd_import
Command to import and manage
GNBDs on a GNBD client.
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.
nanny
The
nanny
monitoring daemon runs on
the active LVS router. Through this
daemon, the active LVS router
determines the health of each real server
and, optionally, monitors its workload. A
separate process runs for each service
defined on each real server.
Fun ct io n Co mp o nen t s Descrip t io n
Red Hat Ent erprise Linux 5 Clust er Suit e Overview
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