Q&A on textdumps (fwd)

[Volker]

On 12/23/-58 20:59, Norberto Meijome wrote:
> On Tue, 1 Apr 2008 12:57:06 +0100 (BST)
> Robert Watson <rwatson at FreeBSD.org> wrote:
> 
>> (7) I'm in DDB and I suddenly realize I want to save the output, and I haven't 
>> configured textdumps. What do I do?
>>
>> As with normal dumps, you must previously have configured support for a dump 
>> partition. These days, that is done automatically whenever you have swap 
>> configured on the box, so unless you're in single-user mode or don't have swap 
>> configured, you should be able to do the following:
> 
> 
> First of all, thanks Robert - I am definitely not capable to debug kernel
> crash, but the fact there are tools out there to make things easier is
> definitely welcome ! :)
> 
> What happens if one encrypts the swap with GELI? Is this the same case as
> "no swap defined" ? I've found back in 6.x that dumps wouldn't work properly
> (I cant remember whether it would dump the data into the current encrypted
> disk, or geli would kick in before savedump on reboot....) Since then I have a
> separate partition for the dumps defined in rc.conf and dumps work ok .

Norberto,

while the system is experiencing a panic, it does not have any knowledge
about filesystems and also does not know about the GELI swap space anymore.

In this situation the geli encrypted swap will be overwritten by a dump
(either minidump or the classical one). When the system boots up again,
it will check $dumpdev for a dump and save it to $savecore before geli
swap is brought up again.

Or in short: geli backed swap should not do you any harm.

Volker