Red Hat CLUSTER SUITE FOR ENTERPRISE LINUX 5.1 Overview page 36

Chapter 1. Red Hat Cluster Suite Overview
Figure 1.19. Components of a Running LVS Cluster
The daemon runs on both the active and passive LVS routers. On the backup LVS
pulse
router, sends a heartbeat to the public interface of the active router to make sure the
pulse
active LVS router is properly functioning. On the active LVS router,
daemon and responds to heartbeat queries from the backup LVS router.
Once started, the
lvs
Virtual Server) routing table in the kernel and starts a
server on each real server. Each
one real server, and tells the
malfunction is detected, the
IPVS routing table.
If the backup LVS router does not receive a response from the active LVS router, it initiates
failover by calling
send_arp
(MAC address) of the backup LVS router, sends a command to the active LVS router via both
the public and private network interfaces to shut down the
router, and starts the
lvs
configured virtual servers.
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daemon calls the
ipvsadm
process checks the state of one configured service on
nanny
daemon if the service on that real server is malfunctioning. If a
lvs
daemon instructs
lvs
to reassign all virtual IP addresses to the NIC hardware addresses
daemon on the backup LVS router to accept requests for the
pulse
utility to configure and maintain the IPVS (IP
process for each configured virtual
nanny
to remove that real server from the
ipvsadm
daemon on the active LVS
lvs
starts the
lvs