optional mounts in fstab?

[Frantisek Hanzlik]

Bill Davidsen wrote:
> Tom Horsley wrote:
>> On Sat, 23 Feb 2013 13:37:29 -0500
>> Bill Davidsen wrote:
>>
>>> Defining the mount as "noauto" doesn't help, the boot still tries to do the
>>> fsck, and still fails. Moreover, I really want the unit mounted if present.
>>
>> The fsck is (I believe) controlled independently from noauto
>> by one of the two obscure numbers on the end of the mount
>> line (which may actually be documented in the fstab
>> man page).
>>
> It is, that's what I was mentioning in the 2nd paragraph, the fsck field
> controls the order in which checks are done before mounting, to be sure that
> mounts on mounts obey the law of least astonishment. (Plauger's Law)
> 
>> Using noauto though means it won't mount it at all. You'd
>> have to do something like put a mount command in /etc/rc.d/rc.local
>> that could simply fail if the device isn't connected.
>>
> Yes, that was an attempt to avoid the hang on boot, what I really need is
> more complex, and I may have to put it in rc.local to make it work, although
> I will test on Fedora using the nofail option. As I look at the RHEL world,
> I expect RHEL7 to be along before too long. Perhaps that would satisfy all
> requirements.
> It depends on what the 'nofail' option does if the UUID is present but
> doesn't pass fsck, is it reported and ignored or does it hang the boot?

I see Centos-6.3 'mount' has already 'nofail' option, then it should
perhaps be in equivalent RHEL (and work with fstab fs_passno=2 as You
want).