conf/163668: fstab 'failok' option has no effect on missing hard drive

[Oleg Baranov]

>Number:         163668
>Category:       conf
>Synopsis:       fstab 'failok' option has no effect on missing hard drive
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Dec 28 13:40:10 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Oleg Baranov
>Release:        8.2-STABLE, 9-STABLE
>Organization:
MARIS AS
>Environment:
FreeBSD  9.0-PRERELEASE FreeBSD 9.0-PRERELEASE #1: Wed Dec 28 16:59:09 MSK 2011     root at bsd-gw:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
System drops to Single mode on boot in case special device is missing even corresponding filesystem is marked as 'failok' in /etc/fstab.

Thus server cannot boot becomes remotely unaccessible even if some unimportant drive is missing (or got corrupted and undetectable).

fstab(5) documentation mentions:
"If the option ``failok'' is specified, the system will ignore any error
     which happens during the mount of that filesystem, which would otherwise
     cause the system to drop into single user mode.
"
I fill this behavior as a bug suggesting a server must withstand minor failures as long as it can and definitely should not get rendered totally useles in case of some secondary (non-root in general) drive/filesystem fault. It should be up to server admin to define those 'secondary' filesystems. 'failok' option has been designed for this particular purpose as far as I understand.


Part of boot log from a faulty system:
-----------------------------
Starting file system checks:
/dev/ada0p2: FILE SYSTEM CLEAN; SKIPPING CHECKS
/dev/ada0p2: clean, 50085826 free (6626 frags, 6259900 blocks, 0.0% fragmentatio
n)
Mounting local file systems:mount: /dev/ufs/botva : No such file or directory
>How-To-Repeat:
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: