Old PC forgets about it's own swap partition & mount it. Need help to write a script

Old_Fogie · 06-29-2006, 04:21 PM

Hi all,

For some reason, over the last two weeks my swap partition on dev/hda2 does not get mounted. On bootup before I even get to /etc/rc.d/rc.pcmcia in the boot process, I sometimes get the warning 'unable to find swap space signature' and therefore the pc does activate the 'swapon /dev/hda2'

I verify this is happening by typing 'top' in console.

Once I type 'mkswap /dev/hda2' then 'swapon /dev/hda2' I'm fine.

Is there a way that I can write a script to verify the existence of the swap partition, and if it does not do this then it will type those commands out for me?

I totally dumped the hard drive, I ran a 'debug script' too. Then reloaded, and it still happens, let's say 1 out of every 2 boots.

I do have the swap file correctly keyed into my etc/fstab.

Any thoughts on how I make a script to check this out for me?

thank you in advance.

Samoth · 06-29-2006, 04:49 PM

you could make a script to check "free" and find out if you have any swap. If you dont see any swap then you can turn the swap on.

Another thing, you mention both swap file and swap partition in your post....which one is it(they are most different)? I am led to believe it is a partition, but still....

<<Samoth>>

bathory · 06-29-2006, 06:28 PM

You can use /proc/swaps to see if swap is activated. Try a script like this:

Code:

#!/bin/sh

if grep -q "/dev/hda2" /proc/swaps; then
echo "swap already ok"
else
/sbin/swapon -a
echo "swap is now ok"
fi

If you need to re-format /dev/hda2, add "/sbin/mkswap /dev/hda2" before swapon.

Regards

Old_Fogie · 06-29-2006, 07:14 PM

samoth: you are correct, i said swap file near the end of my post there initially. I did mean "swap partition on /dev/hda"

bathory: i'll give it a shot in a little while and report back.

thanks guys.,

Old_Fogie · 06-30-2006, 01:39 PM

Wouldn't you know I've rebooted this pc about 10 times, and it hasn't forgotten to add the swap partition so I cant verify if the fix works yet or not. LOL

I tell ya, sometimes computers have minds all their own.

Old_Fogie · 06-30-2006, 11:52 PM

bathory I made a *.sh file and told my /etc/rc.d/rc.local file to execute it on loading up.

I typed out exactly what you had there and also chmod it too.

Finally today, it booted up and did NOT see the swap partition, but it still said "swap already ok" like the script calls for.

I think it is not accurately checking the status of the existence of an active swap partition.

Any other ideas how the script could properly detect the status/existence accurately of the swap partition?

Or did I put my script in the wrong place?

Thank you again.

bathory · 07-01-2006, 08:35 AM

When you say you didn't saw the swap partition, what is the output of:

Code:

cat /proc/swaps

And what happens if you run the script manually when you see no swap partition?

onebuck · 07-01-2006, 10:12 AM

Quote:

Originally Posted by Old_Fogie

bathory I made a *.sh file and told my /etc/rc.d/rc.local file to execute it on loading up.

I typed out exactly what you had there and also chmod it too.

Finally today, it booted up and did NOT see the swap partition, but it still said "swap already ok" like the script calls for.

I think it is not accurately checking the status of the existence of an active swap partition.

Any other ideas how the script could properly detect the status/existence accurately of the swap partition?

Or did I put my script in the wrong place?

Thank you again.

Hi,

How about running some HD diagnosis!

What is the output of;

Code:

#hdparm -I /dev/hd?         #replace ? with your device

Old_Fogie · 07-03-2006, 12:48 AM

cat /proc/swaps gives me the following IF the swap partition is activated upon boot:

Filename Type Size Used Priority
/dev/hda2 partition 514072 668 -1

and the hdparm -i /dev/hda gives me:

Model=TOSHIBA MK6409MAV, FwRev=F5.01 A, SerialNo=
Config={ Fixed }
RawCHS=13424/15/63, TrkSize=0, SectSize=0, ECCbytes=36
BuffType=unknown, BuffSize=0kB, MaxMultSect=16, MultSect=16
CurCHS=13424/15/63, CurSects=12685680, LBA=yes, LBAsects=12685680
IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: sdma0 sdma1 sdma2 mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 *udma2
AdvancedPM=no WriteCache=enabled
Drive conforms to: device does not report version: 1 2 3 4

* signifies the current active mode

bathory · 07-03-2006, 03:47 AM

The script should work (I've tested it by deactivating my swap partitionan then runing the script to re-activate it). If swap is not activated then /proc/swaps is empty, else it contains what you've posted. I suggest you to remove it from rc.local and run it manually when you see no swap space to see what happens.

Old_Fogie · 07-08-2006, 06:19 AM

Hi bathory,

I found in the /etc/rc.d/rc.0 script some "sleep" times related to turning off the local hard drives, turning off swap, and performing something called "sync".

Anyway, I just increased the sleep times, actually I just double all of them, and so far so good.

So far it looks like that may?? have been my issue on this old slow laptop. I'll post back if the issue rears it's ugly head, but so far so good. Thank you again for your replies, it is really appreciated.