Piranha Configuration Tool - Red Hat ENTERPRISE LINUX 4 Manual

Function Components
lvsd
ipvsadm
nanny
lvs.cf

Piranha Configuration Tool

Cluster Components
Description
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.
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.
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.
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.
This is the LVS configuration file. The full
path for the file is /etc/sysconfig/
ha/lvs.cf. Directly or indirectly,
all daemons get their configuration
information from this file.
This is the Web-based tool for
monitoring, configuring, and
administering LVS. This is the default
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