[All Linux Operating Systems]When a SAN host loses access to all paths to a boot LUN, Linux marks the filesystem on the client as read-only.
Linux can lose all paths to a boot LUN. When a SAN host loses access to all paths to a boot LUN, to prevent data corruption, the Linux system marks the filesystem on the client as read-only. This behavior is as designed and occurs regardless of whether the Oracle FS Path Manager (FSPM) is installed on the SAN host. To improve the path recovery time, Oracle recommends that you take the following action: modify the /etc/multipath.conf file and set failback immediate.