iSCSI timeout configuration settings for the system

You can set the timeout value for disks.

The disk timeout is set in the /sys/block/<device>/device/timeout file. Depending on operating system and OS version, increase the default value of 30 or 60 seconds to 120 in most situations.

For example, if the device is /dev/sdc, you would use:

[root@R64SRV6 ~]#echo -n 60 > /sys/block/sdc/device/timeout

To increase the SCSI command timeout for the system, create the following udev rule so that it is not necessary to set the timeout manually for each mapped disk:

udev rules file
cat /etc/udev/rules.d/99-ibm-2145.rules

# Set SCSI command timeout to 120s (default == 30 or 60) for IBM 2145 devices
SUBSYSTEM=="block", ACTION=="add", ENV{ID_VENDOR}=="IBM",
ENV{ID_MODEL}=="2145", RUN+="/bin/sh -c 'echo 120 > /sys/block/%k/device/timeout'"

Reconfirm the settings after your restart the system. After you set up your volumes, use multipath -ll | grep sd to locate the block device paths. Also, check with cat /sys/block/sd<x>/device/timeout for 120 seconds, where <x> is a 2145 path. For example:

edam:~ # multipath -ll | grep sd | tail -1
  `- 10:0:0:4 sdl 8:176 active ready running
edam:~ # cat /sys/class/block/sdl/device/timeout
120
edam:~ #