Red Hat LINUX VIRTUAL SERVER 5.1 - ADMINISTRATION Manual page 23

Figure 1.5. LVS Components
The daemon runs on both the active and passive LVS routers. On the backup router,
pulse
sends a heartbeat to the public interface of the active router to make sure the active
pulse
router is still properly functioning. On the active router,
responds to heartbeat queries from the backup LVS router.
Once started, the
lvs
routing table in the kernel and starts a
real server. Each
nanny
and tells the daemon if the service on that real server is malfunctioning. If a malfunction is
lvs
detected, the daemon instructs
lvs
table.
If the backup router does not receive a response from the active router, it initiates failover by
calling to reassign all virtual IP addresses to the NIC hardware addresses (MAC
send_arp
address) of the backup node, sends a command to the active router via both the public and
private network interfaces to shut down the
daemon on the backup node to accept requests for the configured virtual servers.
daemon calls the
ipvsadm
nanny
process checks the state of one configured service on one real server,
ipvsadm
lvs
starts the
pulse
utility to configure and maintain the IPVS
process for each configured virtual server on each
to remove that real server from the IPVS routing
daemon on the active router, and starts the
LVS Components
daemon and
lvs
lvs
13