Bug 651389

Description of problem:

When dev_loss_tmo is configured to a value of more than 600 in multipath.conf (without setting the fast_io_fail_tmo in multipath.conf), restarting the multipath daemon fails to set the parameter accordingly. Also, setting fast_io_fail_tmo and dev_loss_tmo together in the conf file will not help. After restarting the daemon, running "multipath" also does not help.

To make this work, first fast_io_fail_tmo alone has to be set in multipath.conf and the daemon should be restared. Then, dev_loss_tmo configuration has to be added to the multipath.conf and again, the daemon should be restarted.

This issue is known as per the comment - https://bugzilla.redhat.com/show_bug.cgi?id=634589#c30 .

Secondly, if dev_loss_tmo is not allowed to be set beyond 600 seconds without setting fast_io_fail_tmo, multipath or multipathd daemon should throw a warning/error message or log the failure in syslog.


Version-Release number of selected component (if applicable):

RHEL6.0 GA (2.6.32-71.el6)
device-mapper-multipath-0.4.9-31.el6


How reproducible:
Always


Steps to Reproduce:
1. Configure the following settings in defaults section of multipath.conf:
       fast_io_fail_tmo 10
       dev_loss_tmo    601
2. Restart the multipathd daemon (or reboot the host).
3. Check the dev_loss_tmo values for the remote FC ports in sysfs:

    # ls /sys/class/fc_remote_ports/rport-*\:*-*/dev_loss_tmo
    /sys/class/fc_remote_ports/rport-0:0-0/dev_loss_tmo    
    /sys/class/fc_remote_ports/rport-1:0-0/dev_loss_tmo    
    /sys/class/fc_remote_ports/rport-0:0-1/dev_loss_tmo    
    /sys/class/fc_remote_ports/rport-1:0-1/dev_loss_tmo

    # cat /sys/class/fc_remote_ports/rport-*\:*-*/dev_loss_tmo
    30
    30
    30
    30

Actual results:
The dev_loss_tmo parameter is not set properly.

Expected results:
The parameter should be set as expected.

Additional info:

The full multipath.conf looks like below:

defaults {
        fast_io_fail_tmo  10
        dev_loss_tmo      601
}

blacklist {
    devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
    devnode "^hd[a-z]"
    devnode "^dcssblk[0-9]*"
    wwid    35000cca0070ad359
}

devices {
        device{
               vendor "NETAPP"
               path_grouping_policy group_by_prio
               features "1 queue_if_no_path"
               prio "ontap"
               path_checker directio
               failback immediate
               hardware_handler "0"
               rr_weight uniform
               rr_min_io   128
               product "LUN.*"
               getuid_callout "/lib/udev/scsi_id -g -u -d /dev/%n"
        }
}