SecurePath Users: Will you be moving to booting from your SAN?

[Alzhy]

Withthe release of SecurePath 3.0D, it is now possible to boot off of SAN disks and EVA disks are now fully supported.

Anyone planning this early to move boot subsystems entirely on SAN disks?

This will have important implications particularly to those employing Virtual Partitions as this would mean a savings in PCI slot.. So, it will now mean more vPars on systems that support it..

But I am still skeptical this early about having all my servers boot off the SAN..

[Mark Grant · Accepted solution]

No, we won't.

It might work but I like to keep my systems as simple as possible. I also want to be able to boot my systems if the EVA goes up in smoke if only so I can plug in as many old disk cabinets as I can and restore to those.

Probably wouldn't never actually do that but it's a nice feeling to know that I can boot a machine without the SAN.

[Alzhy]

Mark. thanks.

And just playing the devils advocate here - you can always boot off your DVD/CDROM or accross the network..

And my initial readings show that indeed path failover among multiple HBA's is also supported on SAN boot environments. The only POF here would be the SAN itself -- but if one has redundant SANs -- ie, dual HBA's, dual Switches, etc.. what could go wrong?

I definitely would wait and somehow agree with your concerns.

[Mark Grant]

You make a good point about the CD/DVD. However, my experience is that when I need to find one of those, I haven't a clue where to look. When I don't need one, I'll find about thirty of them strewn across my desk :)

I also rather like the idea of being able to do an Ignite restore with no SAN available. We keep our DNS, NIS and Data Protector database in vg00 so an Ignite restore gets us a good way to a disaster recovery.

[Bernhard Mueller]

Nelson,

I would agree with Mark that it is a nice feeling to be able to boot from a local disk whatever happens on any FC switches, any disk arrays or any DWDM boxes etc etc.

The early adpoters I know are just about to move their boot disk mirrors into the SAN, but still have the primary boot path set to a local disk.

However, for the majority I believe this is not an option today nor in the near future.
(measured in IT dimensions)

Regards,
Bernhard

[Alzhy]

Thanks once more for your insights/inputs..

I am not really that 'gung-ho' about moving to booting on the SAN but it's just thet the advances in truly fault tolerant SANs are here and real today (whole SAN's can now actually be 'refreshed' without downtime, switches upgraded, changed on the fly and we very well know HBA's on HPUX servers are 'OLAR-able'.

And with servers these days sporting very large memory, the use of the boot disk (no matter where it is at) is virtually relegated to just starting up the OS - with most activity being 'cached' or could be cached. And with advances in optical media or FLASH devices - who knows, servers in the near future will no longer need hard drive storage for booting the OS...

As a matter of analogy, my home PC Server (Linux) boots off its OS from CD-ROM media. I have long ago stopped installing Linux on my hard-drive since practically the OS can be cached in memory. With FLASH devices also increasing in density and affordability (512MB-1GB flash memory are now affordable) - I may plan to boot off flash memory. And who knows, Servers in the near future might actually be using flash memory for the OS.

[Rory R Hammond]

I do not plan to boot from the SAN.
RWDVD's could be used but they would not be fast enough. I think swap and tmp should be on local drives. Where the system process scheduler would have control over the fastest access. Our SAN is shared and access response can be influenced by other systems.

The Fibre HUBs and Switch adds another layer of complexity and possible failure. If I lose access to DATA my system ussally will not crash. If I lose access to system resources, I am rebooting.

FLASH DISK might be an answer. We have some neoware flash disk boxes that run LINUX and are used as dumb terminals and browser access, The seem to work nicely. Currently I don't think the FLASH disk are big enough to hold a large dynamic system. I also would want the FLASH disk to be moveable. I have swap disks to another box when one has died and support was hours a way.

A question in my mind about FLASH: I have read that FLASH has a life expectancy. On a large dynamic system how long is this? and is it longer than Disk?

Rory

[Todd McDaniel_1]

I agree with the sense that you are introducing another point of failure or at least unneeded complexity into the mix.

I can tell you my company will not be doing this...not for a loooong time. NO OS related disk will be on a SAN or any array...neither /tmp nor /home either. Our standard is to have it in the host.

I must say it could be a good way to have a backup (tertiary) boot disk on the SAN, but I wouldnt rely on my primary/secondary boot device being at the mercy of a SAN. Although they are close to .99999 uptime nowadays.



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Unless or until we install Blade servers, which have a small footprint, we will keep the disks local...

One other thing... HP tends not to support disks and H/W outside the Server... so that would be a very bad thing if you lost a boot disk and HP wouldnt replace it b/c you installed in the EMC/HP/Compaq frame!!!