Yes, you will think I'm an evil microsoft supporter, never, but Linux remains just a toy:

Since 2 days we are spending our time to make a "simple" SAN connection on a linux, here is it what we need, a real world study:

  • A real time kernel
  • A SAN connection with 4G Qlogic dual port
  • Multipathing
  • A shared FS over SAN

RHEL/Centos: just a mess to have a real time kernel, everything is complicated, recompile a kernel is like send a man on the moon.
But on RHEL 4, we can see all our 30 LUNs disk, on RHEL5 we can only see 8 LUNs, it seems to be the same on all recents kernel.
But we need a recent kernel to support our recent hardware.

Ubuntu 7.04: I love Ubuntu, but when it comes to do real thing... no way to see the 30 LUNs directly, played with scsi_mod options ... but it never want to show up more than 8 LUNs, we need to add it manually, wonderfull and very professional ;)
By the way after each reboot, the host number of the scsi device is changing ...

We have tested the latest qlogic driver, recompile the kernel etc ... No way, this is not how I want to work, I need something rock solid ..

Install Solaris 10, you have qlogic driver, you have a real time kernel that works, the 30 LUNs shows up, edit one file to enable MPxIO, DONE !
Then use QFS for the shared part

Linux is for student who have the time to play, not for the real world, ok linux fills some gaps: my personal webserver is a linux but it doesn't mean I need to install it everywhere like a virus !

I'm really disappointed, it seems no one is really making SAN, shared FS on linux with recent kernel, show me I'm wrong.

Ok let's be fair, you should ask so why don't you install Solaris ?
Cause I need Jack and some stuffs that only compile on Linux, yes all developpers like Linux (never understand why), this is the only power of linux, everything is made for it.

I hope it will really changes with OpenSolaris.
For the guys who think linux is a religion: wake up guys, there is real world out there.