[SOLVED] fstab, chown or chmod - A partition

[hinto]

If I plug it in - it gets mounted - consider it "made use of" :)

^That's not UUID, that's /dev/sdb.
-Hinto

[bizcuit]

Yeppers Pidsley good point, missed what you'd said about UUID vs /dev and the installer changing the swaps UUID everytime. Have seen that happen often enough and agree it's annoying. At the time only had 3-4 gnu/nix installs. For someone like you, could have who knows how many @ any given time. Could see how it'd drive a person nutz having to go through and correct it.

Of course agree with the don't share a /home. Never tried it, researched it and saw enough warnings and folks advising against it. In the situation Sector's described, each install would have it's own /home partition. Would just be mounted and accessible from the others. Honestly have never tried that myself. Though why wouldn't a /home partition be like any other shared data partition ? All the dotfiles and config files involved would be kept separate ... not shared.


Hope you guys/gals are having a good one. Vllbbq! :)

[hinto]

last I checked, you don't need swap in fstab. Linux automatically mounts it if it finds it.
-H

[bizcuit]

Hmmm interesting, had never heard of that Hinto. That'd be a good solution, so is the one Pidsley went with too. Ah so many ways to skin a penguin. ;)

[Sector11]

^^ @ Hinto ... cool ... I would never have guessed:

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 30 Aug 13 | 16:10:48 ~
    $ par
Partition: ID: / size: 15G used: 4.6G (34%) fs: ext4 dev: /dev/sda1 
           label: N/A uuid: 4fb35957-ffa5-4011-8cae-a3ed9e293c3b
           ID: /media/5 size: 117G used: 34G (31%) fs: ext4 dev: /dev/sda5 
           label: N/A uuid: 4e253402-7c18-4346-85ce-4eaa74877cfb
           ID: /media/10 size: 17G used: 44M (1%) fs: ext4 dev: /dev/sda10 
           label: N/A uuid: 684440b6-4b6c-4082-863b-5bab46e6f21c
           ID: /home size: 15G used: 4.5G (33%) fs: ext4 dev: /dev/sda2 
           label: N/A uuid: fabad1fb-6591-4c27-9b50-2720d9589d64
           ID: /media/bake size: 16G used: 1.6G (11%) fs: ext4 dev: /dev/sda8 
           label: N/A uuid: f667e6ac-b263-4cb1-858e-a768fcb69def
 
 30 Aug 13 | 16:10:51 ~
    $ 

but it is in fstab...

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UUID=12fdb838-a76f-4f29-a0cf-b5cdc6d379ed	none	swap	sw	0	0

... but with a mount point of none.

[hinto]

Try commenting out the fstab entry...
If it works, then yahoo... I'm not quite losing my mind.
BTW... LiveCDs mount swap partitions on a hard drive automatically if they exist.
-Hinto

[Sector11]

Try commenting out the fstab entry...
If it works, then yahoo... I'm not quite losing my mind.
BTW... LiveCDs mount swap partitions on a hard drive automatically if they exist.
-Hinto

Why would I want to comment it out? It's strange that a swap with no mount point is there, I don't know why it is, but meybe like you said, if it's used by Live/CD/USB's it's good to have it there.

[hinto]

LiveCD's don't read your /etc/fstab.
I'll comment it out on mine and do swapoff/swapon.
Back in a sec.
-H

Edit: Looks like LiveCD's are doing a bit of magic by querying for the swap partition UUID, then turning it on. swapon appears to want the /etc/fstab entry.

-Hinto

[Sector11]

OK, noob alert - you lost me with "and do swapoff/swapon"

You commented it out in your fstab... how do you know it turned it on when booting from a LiveCD?
Unless you can slow motion the stuff that flies by ... I have never been able to read that.

[bizcuit]

Example is using sudo again of course. Yeppers as root not needed.

Turn off swap:
"sudo swapoff -a"
Turn swap back on: "sudo swapon -a"

Still an interesting reminder and infobit Hinto, though appears you do need an fstab entry for the swap partition. Remember people mentioning that creating a swap partition would allow people to successfully install a gnu/nix OS on a pc that'd be too low RAM to do it otherwise. Like ya said the installer is supposed to detect and use any swap partition available.

Never actually had to try it but plenty of folks said it's so. How goes the mounting of shared partitions Sector ? Glad Pidsley brought up the installer reformatting swap and assigning a new UUID every time you do an install. It's easy to fix Sector, After installing a new nix OS. Bootup any installs that you've noticed the swap parition is no longer available in. Use the "sudo blkid" to get the new UUID for the swap and then copy/paste the sucker into ea swap borked installs fstab file. Replacing the old swap UUID with the new/correct one and whamo ! You'll have your swap parition working again in that OS.

You only have 2-3 gnu/nix installs but it's still a pain in de arse putting the new swap UUID in ea installs fstab. Never tried it but wonder if someone can mix UUID's and /dev/sdaX in fstab ? If you can, could make sense to use /dev/sdaX for the swap partition ( like Pidsley is doing.) instead of it's dang UUID.

ie: If my swap were on sda5 fstab entry for it would be.

# swap was on /dev/sda5 during installation
/dev/sda5 none swap sw 0 0

Anyone know if it's possible to mix UUID's and /dev/sdaX entries in fstab ? Ah hell I'll try it out myself ... report back a bit later fellas.

Findings: Yep looks like swap is working fine here. At least it's showing up and seems normal when did "free -m", after changing the swap fstab entry to /dev/sdaX. Ha thanks to Pidsley .. Seems like a much better solution for the nix multibooter than having to correct the stinking UUID in all OS's every time the swap partition gets formatted.

[hinto]

UUID only changes if you create a new partition. Reformatting won't change it (or at least it shouldn't)
Check the results next time you install. (I was wrong about not needing the fstab entry. I might be wrong about this, too ;) )
-Hinto

[bizcuit]

No worries Hinto ... we've actually had this convo before in Crunchville Yeppers fellow nixer, have seen the Debian installer format swap and change the the partitions UUID several times. Hopefully it's something that's been corrected between then and now ? Hope you all are having a good night going on.


Vllbbq! :)

[johnraff]

There's another alternative to /dev/* or UUID, labels.
Both /dev names and UUID's can change, but if you give a partition, or usb stick, a label it will stay till you format it. Then you can mount, say, a squeeze partition with the label 'squeeze' with

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sudo mount -L squeeze /path/to/mount

Thunar will display the drive by its label and automounting also usually uses the label name for the mountpoint, which might be handy.
Add labels with gparted or some cli command I forget...

[bizcuit]

So many friggin ways to go with gnu/nix can make a persons head explode ! Thanks John for bringing another option to the table. Plan on leaving fstab as is for now. UUID's for everything except swap and /dev/sdaX for the swap partition. See if anything borks ... :D

My luck there'll be some sweeping change and the OS will suffer borkage ... sighs. Oh well, am well armed with Xaos52's chroot how to if anything does go wrong. Plus a decent trickbag of other good unborkage techniques.

Public service announcement !!! Today is international nix borkage awareness day fellows. Borkage is always lurking ... never forget that ! Of course ^ that is complete bs but borkage can happen @ anytime! D: Toooooo much coffee dang it !

[Sector11]

@ johnraff - this lable thing has peaked my interest. Must look into that...

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$ e2label

maybe ... gotta run?

[xaos52]

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sudo e2label /dev/sdxy label

replace x by the device character, y by partition number and label by the desired label (max 16 chars, better avoid spaces and special characters)

[Sector11]

Perfect thank you johnraff and xaos52

<--- me typo prone 3.5 finger look at the keyboard hunt and peck typist. functions and aliases are my friends.

... A long time ago a friend gave me some sample functions ... soooooooo
I made a bash function:

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## Change or add labels on a Partition #######################################
lpar() {
      sudo e2label /dev/sda$1 $2
}

Since I only have one HDD I used /dev/sda$1, with more /dev/$1 $2 would work I would imagine.

[johnraff]

^Sector, be very careful with using functions for action on drives like this. One little slip, an unmeant space or an unset variable can do serious damage.
eg /dev/sda$1 will revert to /dev/sda if $1 is unset...

[bizcuit]

Just checking in @ the grill. :)

And an update, swap still working fine here using /dev/sdaX for it and UUID's for the other partitions in fstab. At least it's showing up, is the right size etc. So concluding from this brief experiment that mixing UUID's and /dev/sdaX for swap isn't a problem.

Never tried using labels to identify partitions. If anyone has the time or desire. What's the advantages-benefits of assigning labels over UUID or /dev/sdXX ? Regardless hope all the kewl nixers here are having a peach of a dy/nt. Cya's later ...


Vll! :)

[Sector11]

^Sector, be very careful with using functions for action on drives like this. One little slip, an unmeant space or an unset variable can do serious damage.
eg /dev/sda$1 will revert to /dev/sda if $1 is unset...

OH HELL!!!! Kill that function.

Thank You John ....