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if_mpadm(1m) [sunos man page]

if_mpadm(1M)						  System Administration Commands					      if_mpadm(1M)

NAME
if_mpadm - change operational status of interfaces within a multipathing group SYNOPSIS
/usr/sbin/if_mpadm -d interface_name /usr/sbin/if_mpadm -r interface_name DESCRIPTION
Use the if_mpadm utility to change the operational status of interfaces that are part of an IP multipathing group. If the interface is operational, you can use if_mpadm -d to detach or off-line the interface. If the interface is off-lined, use if_mpadm -r to revert it to its original state. When a network interface is off-lined, all network access fails over to a different interface in the IP multipathing group. Any addresses that do not failover are brought down. Network access includes unicast, broadcast, and multicast for IPv4 and unicast and multicast for IPv6. Addresses marked with IFF_NOFAILOVER do not failover. They are marked down. After an interface is off-lined, the system will not use the interface for any outbound or inbound traffic, and the interface can be safely removed from the system without any loss of network access. The if_mpadm utility can be applied only to interfaces that are part of an IP multipathing group. OPTIONS
The if_mpadm utility supports the following options: -d interface_name Detach or off-line the interface specified by interface_name. -r interface_name Reattach or undo the previous detach or off-line operation on the interface specified by interface_name. Unless the -d option was used to detach or off-line the interface, this option will fail. EXAMPLES
Example 1: Detaching an Interface Use the following command to off-line or detach the interface. All network access will failover from hme0 to other interfaces in the same IP multipathing group. If no other interfaces are in the same group, the operation will fail. example% if_mpadm -d hme0 Example 2: Reattaching an Off-line Interface Use the following command to undo the previous operation. Network access will failback to hme0. example% if_mpdadm -r hme0 ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |Interface Stability |Unstable | +-----------------------------+-----------------------------+ SEE ALSO
ifconfig(1M), in.mpathd(1M), attributes(5) DIAGNOSTICS
off-line failed as there is no other functional interface available in the multipathing group for failing over the network access. This message means that other interfaces in the group are failed over already or the multipathing configuration was not suitable for com- pleting a failover. off-line cannot be undone because multipathing configuration is not consistent across all the interfaces in the group. This message means that some interfaces in the IP multipathing group are not configured consistently with other interfaces in the group, for example, one of the interfaces in the group does not have an IFF_NOFAILOVER address. SunOS 5.10 3 Sep 2002 if_mpadm(1M)

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in.mpathd(1M)															     in.mpathd(1M)

NAME
in.mpathd - daemon for network adapter (NIC) failure detection, recovery, automatic failover and failback SYNOPSIS
/usr/lib/inet/in.mpathd The in.mpathd daemon performs Network Interface Card (NIC) failure and repair detection. In the event of a NIC failure, it causes IP net- work access from the failed NIC to failover to a standby NIC, if available, or to any another operational NIC that has been configured as part of the same network multipathing group. Once the failed NIC is repaired, all network access is restored to the repaired NIC. The in.mpathd daemon can detect NIC failure and repair through two methods: by monitoring the IFF_RUNNING flag for each NIC (link-based failure detection), and by sending and receiving ICMP echo requests and replies on each NIC (probe-based failure detection). Link-based failure detection requires no explicit configuration and thus is always enabled (provided the NIC driver supports the feature); probe-based failure detection must be enabled through the configuration of one or more test addresses (described below), but has the benefit of testing the entire NIC send and receive path. If only link-based failure detection is enabled, then the health of the interface is determined solely from the state of the IFF_RUNNING flag. Otherwise, the interface is considered failed if either of the two methods indicate a failure, and repaired once both methods indi- cate the failure has been corrected. Not all interfaces in a group need to be configured with the same failure detection methods. As mentioned above, in order to perform probe-based failure detection in.mpathd needs a special test address on each NIC for the purpose of sending and receiving probes on the NIC. Use the ifconfig command -failover option to configure these test addresses. See ifconfig(1M). The test address must belong to a subnet that is known to the hosts and routers on the link. The in.mpathd daemon can detect NIC failure and repair by two methods, by sending and receiving ICMP echo requests and replies on each NIC, and by monitoring the IFF_RUNNING flag for each NIC. The link state on some models of NIC is indicated by the IFF_RUNNING flag, allowing for faster failure detection when the link goes down. The in.mpathd daemon considers a NIC to have failed if either of the above two meth- ods indicates failure. A NIC is considered to be repaired only if both methods indicate the NIC is repaired. The in.mpathd daemon sends the ICMP echo request probes to on-link routers. If no routers are available, it sends the probes to neighboring hosts. Thus, for network failure detection and repair, there must be at least one neighbor on each link that responds to ICMP echo request probes. in.mpathd works on both IPv4 and IPv6. If IPv4 is plumbed on a NIC, an IPv4 test address is configured on theNIC, and the NIC is configured as part of a network multipathing group, then in.mpathd will start sending ICMP probes on the NIC using IPv4. In the case of IPv6, the link-local address must be configured as the test address. The in.mpathd daemon will not accept a non-link-local address as a test address. If the NIC is part of a multipathing group, and the test address has been configured, then in.mpathd will probe the NIC for failures using IPv6. Even if both the IPv4 and IPv6 protocol streams are plumbed, it is sufficient to configure only one of the two, that is, either an IPv4 test address or an IPv6 test address on a NIC. If only an IPv4 test address is configured, it probes using only ICMPv4. If only an IPv6 test address is configured, it probes using only ICMPv6. If both type test addresses are configured, it probes using both ICMPv4 and ICMPv6. The in.mpathd daemon accesses three variable values in /etc/default/mpathd: FAILURE_DETECTION_TIME, FAILBACK and TRACK_INTER- FACES_ONLY_WITH_GROUPS. The FAILURE_DETECTION_TIME variable specifies the NIC failure detection time for the ICMP echo request probe method of detecting NIC fail- ure. The shorter the failure detection time, the greater the volume of probe traffic. The default value of FAILURE_DETECTION_TIME is 10 seconds. This means that NIC failure will be detected by in.mpathd within 10 seconds. NIC failures detected by the IFF_RUNNING flag being cleared are acted on as soon as the in.mpathd daemon notices the change in the flag. The NIC repair detection time cannot be configured; however, it is defined as double the value of FAILURE_DETECTION_TIME. By default, in.mpathd does failure detection only on NICs that are configured as part of a multipathing group. You can set TRACK_INTER- FACES_ONLY_WITH_GROUPS to no to enable failure detection by in.mpathd on all NICs, even if they are not part of a multipathing group. How- ever, in.mpathd cannot do failover from a failed NIC if it is not part of a multipathing group. The in.mpathd daemon will restore network traffic back to the previously failed NIC, after it has detected a NIC repair. To disable this, set the value of FAILBACK to no in /etc/default/mpathd. /etc/default/mpathd Contains default values used by the in.mpathd daemon. See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsr | +-----------------------------+-----------------------------+ ifconfig(1M), attributes(5), icmp(7P), icmp6(7P), Test address address is not unique; disabling probe based failure detection In order for in.mpathd to perform probe-based failure detection, each configured test address on the system must be unique. Since the IPv6 test address is a link-local address derived from the ethernet address, each NIC must have a unique MAC address. NIC interface_name of group group_name is not plumbed for IPv[4|6] and may affect failover capability All NICs in a multipathing group must be homogeneously plumbed. For example, if a NIC is plumbed for IPv4, then all NICs in the group must be plumbed for IPv4. The streams modules pushed on all NICs must be identical. No test address configured on interface interface_name disabling probe-based failure detection on it In order for in.mpathd to perform probe-based failure detection on a NIC, it must be configured with a test address: IPv4, IPv6, or both. The link has come up on interface_name more than 2 times in the last minute; disabling failback until it stabilizes. In order to prevent interfaces with intermittent hardware, such as a bad cable, from causing repeated failovers and failbacks, in.mpathd does not failback to interfaces with frequently fluctuating link states. Invalid failure detection time assuming default 10000 An invalid value was encountered for FAILURE_DETECTION_TIME in the /etc/default/mpathd file. Too small failure detection time of time assuming minimum 100 The minimum value that can be specified for FAILURE_DETECTION_TIME is currently 100 milliseconds. Invalid value for FAILBACK value Valid values for the boolean variable FAILBACK are yes or no. Invalid value for TRACK_INTERFACES_ONLY_WITH_GROUPS value Valid values for the boolean variable TRACK_INTERFACES_ONLY_WITH_GROUPS are yes or no. Cannot meet requested failure detection time of time ms on (inet[6] interface_name) new failure detection is time ms The round trip time for ICMP probes is higher than necessary to maintain the current failure detection time. The network is probably con- gested or the probe targets are loaded. in.mpathd automatically increases the failure detection time to whatever it can achieve under these conditions. Improved failure detection time time ms on (inet[6] interface_name) The round trip time for ICMP probes has now decreased and in.mpathd has lowered the failure detection time correspondingly. NIC failure detected on interface_name in.mpathd has detected NIC failure on interface_name, and has set the IFF_FAILED flag on NIC interface_name. Successfully failed over from NIC interface_name1 to NIC interface_name2 in.mpathd has caused the network traffic to failover from NIC interface_name1 to NIC interface_name2, which is part of the multipathing group. NIC repair detected on interface_name in.mpathd has detected that NIC interface_name is repaired and operational. If the IFF_FAILED flag on the NIC was previously set, it will be reset. Successfully failed back to NIC interface_name in.mpathd has restored network traffic back to NIC interface_name, which is now repaired and operational. The link has gone down on interface_name in.mpathd has detected that the IFF_RUNNING flag for NIC interface_name has been cleared, indicating the link has gone down. The link has come up on interface_name in.mpathd has detected that the IFF_RUNNING flag for NIC interface_name has been set, indicating the link has come up. 4 May 2004 in.mpathd(1M)

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