Subject: Re: "Root on... dumps on..."
To: Zbigniew Baniewski <firstname.lastname@example.org>
From: Kevin Brunelle <email@example.com>
Date: 11/04/2006 22:21:32
On Saturday 04 November 2006 21:43, Zbigniew Baniewski wrote:
> The generic kernel reports when booting the system:
> "root on wd0h dumps on wd0b"
> Yes, I'm aware "root" means "root filesystem" - but I'm not sure, what kind
> of dumps is mentioned there? "Core dumps"?
> Couldn't find the config file, which has the place for that "dumps" pointed
> - is it fixed directly in the kernel config file, without the possibility
> to change the "dumps partition" to different place (in the other way, than
> kernel recompilation)?
If and when your system panics (crashes) the entire state of memory with
be "dumped" onto your swap partition. This is so that it can be recovered
with savecore and you can debug the problem. You do not want to change the
partition to one which holds valid data as the entire partition would be
destroyed in the case of a panic.
You can change the place savecore will store these dumps when you reboot
(defaults to /var/crash). If this directory does not exist then savecore
will abort and you won't have to worry about these dumps.
It is for this reason that your swap space should at least equal the physical
memory of the machine or you will never be able to get a valid crash dump.
As for changing the paritition (like to wd1b ... I am not sure how to do that
exactly but I know it shoud be able to be done). But there is little
practical reason to do that unless that is the only location with a large
enough swap area. NEVER change it to a partition with a filesystem on it or
one that has information you need... because it will be destroyed.