5.4. Issues with queue_if_no_path feature
features "1 queue_if_no_path" is specified in the
/etc/multipath.conf file, then any process that issues I/O will hang until one or more paths are restored. To avoid this, set the
N parameter in the
/etc/multipath.conf file (where
N is the number of times the system should retry a path).
When you set the
no_path_retry parameter, remove the
features "1 queue_if_no_path" option from the
/etc/multipath.conf file as well. If, however, you are using a multipathed device for which the
features "1 queue_if_no_path" option is set as a compiled-in default, as it is for many SAN devices, you must explicitly add
features "0" to override this default. You can do this by copying the existing devices section for your device from
/etc/multipath.conf and editing it to suit your needs.
If you need to use the
features "1 queue_if_no_path" option and you experience the issue noted here, use the
dmsetup command to edit the policy at runtime for a particular LUN (that is, for which all the paths are unavailable). For example, if you want to change the policy on the multipath device
"fail_if_no_path", execute the following command.
dmsetup message mpathc 0 "fail_if_no_path"
Note that you must specify the
n alias rather than the path.