Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 04-08-2006 Installation Manual page 255

To permanently add multipath IO services to the boot sequence, run the following
command:
insserv boot.multipath multipathd
10.3.3 Querying the Status
Querying the multipath IO status outputs the current status of the multipath maps. To
query the current MPIO status, run multipath -l.
The output is very similar to the one already described in
guration" (page 253), but includes additional information about the state of each priority
group and path:
3600601607cf30e00184589a37a31d911
[size=127 GB][features="0"][hwhandler="1 emc"]
\_ round-robin 0 [active][first]
\_ 1:0:1:2 sdav 66:240
\_ 0:0:1:2 sdr 65:16
\_ round-robin 0 [enabled]
\_ 1:0:0:2 sdag 66:0
\_ 0:0:0:2 sdc 8:32
10.3.4 Tuning the Failover with Specific Host
Bus Adapters
Host bus adapter time-outs are typically set up for non-multipath IO environments,
because the only alternative would be to error out the IO and propagate the error to the
application. However, with Multipath IO, some faults (like cable failures) should be
propagated upwards as fast as possible so that the multipath IO layer can quickly take
action and redirect the IO to another, healthy path.
To configure time-outs for your host bus adapter, add the appropriate options to /etc/
modprobe.conf.local. For the QLogic 2xxx family of host bus adapters, for ex-
ample, the following settings are recommended:
options qla2xxx qlport_down_retry=1 ql2xfailover=0 ql2xretrycount=5
[ready ][active]
[ready ][active]
[ready ][active]
[ready ][active]
Section 10.2, "System Confi-
Multipath IO 255