On Mon, 28 Feb 2005, John Moylan wrote:
> It is nice also that NBD is a mature part of the kernel (first
> incorporated back in 2.1), from my research DRBD is really only a bunch
> Tyan Opteron SMP Mobo with PCI-X
> 2 Opteron 240's
Sounds to me like you intend these systems to IO bound. Tip of the
- dont use SMP for IO bound tasks, unless you know it would be a
benefit. A second CPU waiting for IO usually makes little
- avoiding SMP automatically removes several classes of, SMP
specific, reliability-affecting, bugs.
(this applies particularly when you're going for a more unusual
- dont spec SMP just cause you can.
> striped in hardware and then mirrored onto the second card using S/W RAID.
> 2* Gb Ethernet (channel bonded)
Go for routing at layer-3 instead, if at all possible. You're adding
yet another stack of not-widely-used kernel code into the mix by
going the channel bonding route. Not-widely-used kernel code is often
antithetical to reliability.
(user mode code often is too, indeed software in general seems to be,
but at least user mode code can be restarted without too much fuss,
possibly even by a simple watchdog script.).
1. Oh, let "who wrote the driver?" be your guide when selecting
hardware, if reliability is a concern, along with "And did the vendor
provide specs?". Crap, cheap hardware is sometimes a safer bet if the
drivers were written by a kernel guru of long-standing (particularly
if he/she had access to specs) than hot-poop hardware written by
PS: Apparently ENBD:
" ..... is an industrial-strength version of the Linux kernel NBD. "
no idea whether there's truth in that claim.
Paul Jakma paul at clubi.iepaul at jakma.org Key ID: 64A2FF6A
Children are natural mimics who act like their parents despite every
effort to teach them good manners.
Maintained by the ILUG website team. The aim of Linux.ie is to
support and help commercial and private users of Linux in Ireland. You can
display ILUG news in your own webpages, read backend
information to find out how. Networking services kindly provided by HEAnet, server kindly donated by
Dell. Linux is a trademark of Linus Torvalds,
used with permission. No penguins were harmed in the production or maintenance
of this highly praised website. Looking for the
Indian Linux Users' Group? Try here. If you've read all this and aren't a lawyer: you should be!