cmmodnet(1m)cmmodnet(1m)NAMEcmmodnet - add or remove an address or check whether an address can be
added to a subnet or enable or disable a LAN interface in a high avail‐
ability cluster
SYNOPSIScmmodnet [-v] {-a|-r|-t} -i { IPv4_address IPv4_subnet | IPv6_address
IPv6_subnet}
cmmodnet [-v] {-d|-e} LAN_name
DESCRIPTIONcmmodnet is used in certain high availability utilities, such as pack‐
age control scripts and SGeRAC utility scripts for VIP management, to
add or remove an IPv4 or IPv6 address to or from network interface con‐
nected to the subnet identified by subnet_name. In addition, cmmodnet
can be used to check if an IPv4 or IPv6 address can be added to the
given subnet identified by subnet_name.
cmmodnet can also be used to disable or enable a LAN interface cur‐
rently configured in a cluster. HP-UX examples of LAN_name can be
lan0, lan1; Linux examples of LAN_name can be eth0, bond0. This com‐
mand simulates a LAN interface failure or recovery in the cluster with‐
out changing the physical status of the interface.
cmmodnet requires the user be a superuser(UID=0) or have an access pol‐
icy of FULL_ADMIN allowed in the cluster configuration file. Non-supe‐
rusers may only use this command to remove IP addresses. See access
policy in cmquerycl (1m) or cmmakepkg (1m).
Extreme caution should be exercised when executing this command (for
puposes other than checking) outside the context of a package control
script or SGeRAC utility script. In this capacity it should only be
used to remove the relocatable IPv4 or IPv6 addresses of packages which
have failed and are in the "halted" state or to disable and enable a
LAN interface when absolutely necessary. Using it while the package is
running could lead to loss of client connectivity.
The user needs to make sure that an IPv6 subnet must be either site-
local or global and must not be link-local.
Options
cmmodnet supports the following options:
-v Verbose output will be displayed.
-a Add the IPv4_address to the IPv4_subnet or add the
IPv6_address to the IPv6_subnet
-r Remove the IPv4_address from the IPv4_subnet or remove the
IPv6_address from the IPv6_subnet
-t Check only. Checks if the IPv4_address can be added to the
IPv4_subnet or checks if the IPv6_address can be added to
the IPv6_subnet
-i IPv4_Address or IPv6_address
Use the IP address given for the operation. This is a required
parameter.
-d Disable LAN interface configured in the cluster. This
option simulates the LAN interface failure without actu‐
ally bringing the interface down. There is no immediate
effect if the LAN interface is already disabled or physi‐
cally down.
This option allows failover of IP addresses configured in
this LAN interface to an available standby interface (HP-
UX only). If no standby is available (HP-UX and Linux),
the subnet(s) on this interface will virtually go down
and packages monitoring the subnet(s) will be brought
down or switched to another node; in the worst case a TOC
could result if this is a failfast package. This option
also implies that there is no effect on recovery of IP
addresses and subnet(s) on this LAN interface if the
physical status of the interface changes at later time.
-e Enable LAN interface configured in the cluster. This
option simulates a LAN interface recovery from previously
disabled state. There is no immediate effect if the LAN
interface is already enabled or physically down.
RETURN VALUEcmmodnet returns the following values:
0 Successful completion.
1 Command failed.
AUTHORcmmodnet was developed by HP.
SEE ALSOcmhaltserv(1m), cmmakepkg(1m), cmquerycl(1m), cmrunserv(1m).
Requires Optional Serviceguard Software cmmodnet(1m)