Managing HP Serviceguard A.11.20.20 for Linux, March 2014

Table 4 Error Conditions and Package Movement for Failover Packages (continued)
ResultsPackage Error Condition
Package
Allowed to Run
on Alternate
Node
Package Allowed to
Run on Primary
Node after Error
Halt script
runs after
Error or Exit
Linux Status
on Primary
after Error
Service
Failfast
Enabled
Node Failfast
Enabled
Error or Exit Code
YesYesYesRunningEither SettingNoLoss of Network
Yes if
dependency met
Yes when
dependency is
again met
YesRunningEither SettingEither Settingpackage
depended on
failed
3.5 How the Network Manager Works
The purpose of the network manager is to detect and recover from network card failures so that
network services remain highly available to clients. In practice, this means assigning IP addresses
for each package to LAN interfaces on the node where the package is running and monitoring
the health of all interfaces, switching them when necessary.
NOTE: Serviceguard monitors the health of the network interfaces (NICs) and can monitor the
IP level (layer 3) network.
3.5.1 Stationary and Relocatable IP Addresses and Monitored Subnets
Each node (host system) should have an IP address for each active network interface. This address,
known as a stationary IP address, is configured in the file
/etc/sysconfig/network-scripts/ifcfg-<interface> on Red Hat or
/etc/sysconfig/network/ifcfg-<mac_address> on SUSE. The stationary IP address is
not associated with packages, and it is not transferable to another node.
Stationary IP addresses are used to transmit data, heartbeat messages (described under “How the
Cluster Manager Works ” (page 38)), or both. They are configured into the cluster via the cluster
configuration file; see the entries for HEARTBEAT_IP and STATIONARY_IP under “Cluster
Configuration Parameters ” (page 90).
Serviceguard monitors the subnets represented by these IP addresses. They are referred to as
monitored subnets, and you can see their status at any time in the output of the cmviewcl
command; see “Network Status” (page 202) for an example.
You can also configure these subnets to be monitored for packages, using the monitored_subnet
parameter in the package configuration file (page 181). A package will not start on a node unless
the subnet(s) identified by monitored_subnet in its package configuration file are up and
reachable from that node.
IMPORTANT: Any subnet identified as a monitored_subnet in the package configuration file
must be configured into the cluster via NETWORK_INTERFACE and either STATIONARY_IP or
HEARTBEAT_IP in the cluster configuration file. See “Cluster Configuration Parameters ” (page 90)
and “Package Parameter Explanations” (page 174).
In addition to the stationary IP address, you normally assign one or more unique IP addresses to
each package. The package IP address is assigned to a LAN interface when the package starts
up.
The IP addresses associated with a package are called relocatable IP addresses (also known as
IP aliases, package IP addresses or floating IP addresses) because the addresses can actually move
from one cluster node to another. You can use up to 200 relocatable IP addresses in a cluster
spread over as many as 300 packages. These addresses can be IPv4, IPv6, or a combination of
both address families.
62 Understanding Serviceguard Software Components