Re: RAM distribution catch-22, 2 old P1 generation PCs

[Stuart Henderson <stu_(_at_)_spacehopper_(_dot_)_org>]

On 2005/02/14 01:55:17, Jens Ropers wrote:
> Many thanks for your reply and suggestions -- only this had me somewhat 
> puzzled:
> 
> On 14 Feb 2005, at 01:17, Stuart Henderson wrote:
> 
> >With enough RAM that you don't need to swap, and switching off the
> >HD at idle (and reducing crontab) or replacing it with 8-16mb CF and
> >an IDE adapter) you would significantly drop power use and increase
> >the firewall's life expectancy than using normal HD.
> 
> If I'm not misunderstanding you, you're proposing that I use a Compact 
> Flash card in lieu of an actual hard drive? Surely 8-16MB can't be 
> enough for an OpenBSD 3.6 install? Or are you proposing using custom 
> kernel?

A custom kernel and installation with just what's needed for
firewalling, routing, VPN etc. Several people have produced systems
for building these automatically from a list of wanted files.
Flash cards are IDE-compatible, you just need something to connect
pins to the right place, there are plenty of cheap adapters for
this available, probably something around 15 EUR.

A typical flashboot kernel is around 6mb gzipped, including the
userland. It's quite an elegant solution, when you come to upgrade
there's just one file to install, and you can easily keep several
versions to roll back to an earlier one if there's any problem.

flashdist uses a more standard, but stripped-down, installation
using standard filesystem on the CF to hold the userland. This has
the advantage of using less system RAM. You can use a standard
kernel for this, but that might be difficult on 16mb RAM.

They're quite common on SBCs, especially Soekris, but are equally
applicable to small installations on standard PCs (I have a couple
of DNS servers on normal 1U servers diskless running from ramdisk,
pulling their config from a master server, and quite a few
Soekris-based firewalls and VPN routers).