best practices - partitioning, file system types for Alt-F

[shredhead]

So I've been using Alt-F for some time now, and quite happy with it though I have been searching for ways to increase performance. 

I installed it onto a DNS323 that had data on it already. The setup was pretty automatic if I remember correctly. What I ended up with is sda4 and sdb4, both around .5 GB and md0 which is a mirror containing the remaining space of 700GB or so. All three were ext2. I don't know why things were split up like that. I don't know that it's a bad thing, other than the fact that there is some space I never get to use since my data all resides on md0. 

I noticed that fsck had not been running automatically per my settings. When I tried manually, it won't umount md0, therefore it won't do it unless I force fsck on reboot. (Prior to this the thing was running for 6 months straight with no reboot.) Could this be because the Alt-F directory is on md0? 

I then read some info about other file systems. I figured maybe if I convert to ext4 I could get a bit more performance, though I wasn't sure about keeping journaling turned on. I mostly archive data to this NAS, so that seemed like it would not be a big benefit to me. I set out to convert to ext4. The two small mounts/file systems converted fine. The md0 would not umount, therefore would not convert. When I did umount -l it umounted but still would not convert saying the file system was in use. I don't want to lose data so I've paused here to get more information.

Do most people put their data somewhere separate, e.g. making an md1 and moving Home and other things there, keeping Alt-F on md0 ? Maybe that's better for me if converting md0 is impossible?  

Looking for some tips here..   thanks!

[Joao Cardoso]

On Sunday, September 2, 2012 5:56:38 PM UTC+1, shredhead wrote:

So I've been using Alt-F for some time now, and quite happy with it though I have been searching for ways to increase performance. 

I installed

flashed?

 

it onto a DNS323 that had data on it already. The setup was pretty automatic if I remember correctly. What I ended up with is sda4 and sdb4, both around .5 GB and md0 which is a mirror containing the remaining space of 700GB or so. All three were ext2. I don't know why things were split up like that.

D-Link did it.

 

I don't know that it's a bad thing, other than the fact that there is some space I never get to use since my data all resides on md0. 

I noticed that fsck had not been running automatically per my settings.

hmmm, logs?

 

When I tried manually, it won't umount md0, therefore it won't do it unless I force fsck on reboot. (Prior to this the thing was running for 6 months straight with no reboot.) Could this be because the Alt-F directory is on md0? 

Probably. If services are running from there, the filesystem can't be umounted. But at boot time no service is running, it should be able to do the fsck -- the mount is done after fsck is run. Probably the fs needs manual intervention, search the logs.

 

I then read some info about other file systems. I figured maybe if I convert to ext4 I could get a bit more performance, though I wasn't sure about keeping journaling turned on. I mostly archive data to this NAS, so that seemed like it would not be a big benefit to me. I set out to convert to ext4.

Converting implies a successful fsck, so no luck. You have to fix the problem first.

 

The two small mounts/file systems converted fine. The md0 would not umount, therefore would not convert. When I did umount -l it umounted but still would not convert saying the file system was in use. I don't want to lose data so I've paused here to get more information.

Do most people put their data somewhere separate, e.g. making an md1 and moving Home and other things there, keeping Alt-F on md0 ? Maybe that's better for me if converting md0 is impossible?  

Personally, I use sda4/sdb4 for Alt-F and ffp packages. Still, look at the boot logs, as fsck at boot time should be possible, as fs are not yet mounted.

[shredhead]

yes, I flashed it.  fsck does run on reboot though it shows clean on one screen in the gui and dirty in another. 

So it's sort of a catch 22. If I want Alt-F to be on a mirror, then I can never fsck unless I reboot periodically. If I want to convert the file system of the mirrored partition I have to move Alt-F to another location. If I wanted to move Alt-F, how would I even go about that? Is it just a matter of changing the symlink /Alt-F to point to the new location?

[Joao Cardoso]

On Tuesday, September 4, 2012 1:06:19 PM UTC+1, shredhead wrote:

yes, I flashed it.  fsck does run on reboot though it shows clean on one screen in the gui and dirty in another. 

Please clarify. A copy/paste or screen shot.

Remember that ext2 will always shows (by design?) as "dirty".

When you try to  "check" md0 using Disk->Filesystem->FS Operations, doesn't a message appears saying "Couldn't unmount /dev/md0 for checking it, stop services first."? Than you have to stop services first.

So it's sort of a catch 22. If I want Alt-F to be on a mirror, then I can never fsck unless I reboot periodically. If I want to convert the file system of the mirrored partition I have to move Alt-F to another location.

For checking or converting, the filesystem can't be in use. I believe that if all services running from Alt-F installed packages are stopped, than you can check/convert filesystems -- I have done it just now on sda4, where my Alt-F packages directory is located. Of course no Alt-F package installed service was running.

 

If I wanted to move Alt-F, how would I even go about that? Is it just a matter of changing the symlink /Alt-F to point to the new location?

No.

If you really want to do that, again you have to be sure that no Alt-F package service is running, e.g

rcminidlna stop # in general, 'rc<service> stop', use 'rcall status' to see which are running

rcminidlna status # be sure! some services are slow to stop

Then, at the command line:

aufs.sh # to see its usage message

aufs.sh -l # shows where Alt-F packages are installed '/mnt/sda4/Alt-F' for me

aufs.sh -u # don't continue if any error is displayed!

mv /mnt/<current_Alt-F_FS_root>/Alt-F /mnt/<whatever_FS_root>/  # HAS to be a FS root! 

rm /Alt-F

ln -s /mnt/<whatever_FS_root>/Alt-F /Alt-F

aufs.sh -m

Untested, you will void your warranty if you follow it :-)

[shredhead]

I thought I'd share how things went...

You can't turn off ALL services. inetd is still needed and if you try to kill dropbear it kicks you off your ssh connection. when you connect back in it's running. no big deal but I thought I'd mention it. 

Moving the Alt-F location went ok, though I ended up having to reboot to make the aufs.sh -m work. Rebooting wasn't a problem except for the fact that I'd previously put a forcefsck file in the root. So I had to wait for fsck to finish before I could do anything. 

I noticed that the users directory was on sdb4 (why is this?) and thought Alt-F should go on sdb4 as well, then I'd simply do a scheduled backup to sda4. What I noted was that sda4 mounts first, so I then decided sda4 was a better place for Alt-F and went through the move procedure a second time. 

[Joao Cardoso]

On Saturday, September 8, 2012 8:54:04 AM UTC+1, shredhead wrote:

I thought I'd share how things went...

Thanks

 

You can't turn off ALL services. inetd is still needed and if you try to kill dropbear it kicks you off your ssh connection. when you connect back in it's running. no big deal but I thought I'd mention it. 

Thanks. That's why I didn't told you to use 'rcall stop'. Instead you should use 'rcall status' and then 'rc<service> stop' on selected services.

 

Moving the Alt-F location went ok, though I ended up having to reboot to make the aufs.sh -m work.

Do you remember what the error message/symptom was?

 

Rebooting wasn't a problem except for the fact that I'd previously put a forcefsck file in the root. So I had to wait for fsck to finish before I could do anything. 

I noticed that the users directory was on sdb4 (why is this?)

You selected it when adding an user for the first time.

 

and thought Alt-F should go on sdb4 as well, then I'd simply do a scheduled backup to sda4. What I noted was that sda4 mounts first, so I then decided sda4 was a better place for Alt-F and went through the move procedure a second time. 

Yes, filesystems are mounted/used as they are discovered by the kernel, that's why the first partition on a disk has to be a swap partition, so that there is enough "memory" to do a fsck on subsequent filesystems.