Topic: SME5 constant disk activity!?

[Patrick Basile]

Hello everyone,

I just installed SME5 on a "fresh" hard disk, actually two hard drives - I set up RAID1 software mirror during the installation.  This machine is setup as a gateway and server.  The setup went smooth, and I have installed 'Update 2' via the Blades panel in server manager.  All in all things seem ok, and I am getting ready to add my additional RPM's now, ie fetchmail, samba 2.2.1a, etc.

Here's the question - why is there constant hard disk activity on the server?  At the moment, I have only the SME5 server and one other machine on the same network, so it's not that some other machine is accessing it.  Here's the pattern (so I assume it's some background process or application) - the drive activity "light" goes on for 4-5 seconds, then off for about 1 second, then on for 4-5 seconds, then off for about 1 second....and so on, and so on.

What am I missing?  Is there a command to run to find out what has the drive working so often?

Thanks for your help.

Regards,
Patrick

[Andrew Roberts]

Could this activity be the raid array synchronizing?  This can take quite a long time to complete and would result in a lot of disk activity.  You can see the status of the raid by looking at cat /proc/mdstat .

[Patrick Basile]

Andrew,

Thanks for the tip...you hit the nail right on the head!  When I run the cat /proc/mdstat I get the following output:

[root@bcsrv2 /root]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md2 : active raid1 hdb1[1] hda1[0] 264960 blocks [2/2] [UU] resync=DELAYED
md0 : active raid1 hdb5[1] hda5[0] 15936 blocks [2/2] [UU]
md1 : active raid1 hdb6[1] hda6[0] 32740352 blocks [2/2] [UU] resync=2% finish=308.6min
unused devices:
[root@bcsrv2 /root]#

Now I have another question - why is it resynchronizing?  This was a new installation of SME5, so I assumed that it would wipe the old drives clean and start from scratch.  When I setup e-smith 4.1.2 with RAID1 I didn't notice the resynchronzing (although it may have happened).

Is this a 'normal' process when installing SME5 and a RAID1 array?

Thanks a lot for your help!

Regards,
Patrick

[Patrick Basile]

Oh, one other thing...

Is it possible to setup a RAID1 array in SME5 using the 'high speed' setting for better disk performance?  If so, can it be done on large Maxtor 7200rpm 40gb drives?  (I'm using a PII-350 machine, built circa 1998.)  I didn't notice the option when I ran the installation last night, and I think it was during the install of 4.1.2 that the question was asked.

I'll do a search here on the boards for hdparm is guess to see what others have experienced, but any help in this area would be appreciated.

Regards,
Patrick

[Andrew Roberts]

Patrick,

I'm not 100% sure _why_ it needs to sync like that.  I suspect that the initial install gets put on a single disk, and the data is written to the other disk after the initial boot.  You may want to check out one of the RAID howtos on linuxdoc.org or something similar.

I can't comment on SME5 as I haven't had a chance to d/l and burn the iso yet.  Perhaps this weekend.