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Configure RAID and Create Dell Service Partition

1. Install Dell Installation CD in DVD drive and reboot the server with Ctrl-Alt-Del.
   • Note: booting form Dell CD/DVD is slow and sometimes it looks like the server died. Be patient...
      
2. Configure the drives into RAID id you plan to use RAID (if you have just 4 drives and want two separate logical drives you can use Raid 1 or 10 depending on the capabilities of the controller and the level of your love for RAID 10 ;-)

   Note: If you changed RAID configuration using controller BIOS you need go to the creation of a service partition as it looks like Dell startup disk write signatures on the disks and reboot the system. You can delete it later if you do not want it (it is actually very small).

   Usually PE1950/2950 servers are  usually ordered with  4 drives if there is no NAS and 2 drives if  NAS is used. We will discuss "no-NAS" configuration here.

   The typical solution is simple mirroring as drives are cheap: that greatly simplifies maintenance and slightly increases speed of I/O. With the current size of harddrives RAID 1 is the simplest and probably most reliable RAID configuration. 

   Typically we create 2 virtual drives (again, I would like to stress that you do not need to worry about size of the drives those day; if you do just order bigger drives).
    

   • Disks 1,2 The first pair is usually used for OS and should consist of  two  73G drives (or rarely larger, if for example you need an extra-large /var partition). This is more then enough for all OS-related partitions. 36G drives are also OK but home directories might be a little bit tight. Generally those drives should be high speed (15K RPM). As amount of writing on those drive is tiny (and can be further cut by moving /var and /tmp partitions) it would be interesting to experiment with X25-E solid state drives when they are available.
     • Notes:
       • In case you use 36G drive only /var and /home partitions should be separate. Everything else (/usr, /opt ) can be on root partition. This is also acceprable configuration for 73G drives.
       • It make sense to make /usr/local a symbolic link to /opt. That permits to use smaller /usr and more convenient navigation to files in this directory hierarchy.
          
       • If you use fast initialization in RAID controller to create a mirrored pair you need to use Dell disk to write special signatures on the drives. Otherwise they will not be bootable.
          
       • Default options provided by Dell RAID controller called PERC (PowerEdge Expandable RAID Controller ) are usually OK. 
          
       • PERC 6i has  either 256 or 512 M of RAM (PERC 6E ) while 5i has 256M of RAM. The more RAM the better. PERC 6 controllers also include a battery backup unit to protect data in the controller cache during a system power and/or controller failure so you can you more permissive disk writing policy
          
   • Disks 3,4 usually store application partition(s) mounted at application-specific mount point(s). If NAS storage used for application those are essentially redundant. If, by chance, are present should be used for swap and home directories
      
3. Create Dell service partition.   
   • Run Dell utility for creation of service partition until it will do 10% and then stop it by power recycling (you need to keep power key on PowerEdge server until power will switch off).
   • If it runs to 20% it will ask for Suse DVD but will not accept it so you can reboot the server at this time but it is unclear it makes sense to wait.
   • Note: this is a clumsy way, you can do it with any partitioning utility that provides ability to assign arbitrary partition types and then copy Ghost image of the partition