[Info-vax] satellite with more than one boot server

[Bob Koehler]

In article <kegbhc$jcb$2 at online.de>, helbig at astro.multiCLOTHESvax.de (Phillip Helbig---undress to reply) writes:

> First, somewhat unrelated: any boot server can serve the MOP downoad 
> request, whether or not the satellite boots from it, right?

   Any MOP server that is serving MOP in the cluster can download the
   image.  Any disk server that is serving the system disk can
   complete the boot service.

> 
> Is there any reason not to configure a satellite to boot from more than 
> one boot server in a given cluster?

   Having more than one provides redundancy, you can set up the
   satellite so that it can run while either server is down.

> Is there a better way to do this than setting up identical 
> configurations on each bootserver node?  (Note: In this post, and in my 
> cluster, each boot server has its own system disk.)

   It would be best for redundancy if the satellite's system disk was
   dual-pathed to two disk servers.  If you setup two identical
   environments on two served disks you need to be able to tolerate
   the system booting to either one.  If you setup one environment
   on a non-dual pathed disk, any MOP server can honor the initial
   load but that disk server will have to be up to complete the boot.
   (The system disk name is part of the MOP data sent to the satellite.)

> If I replace a satellite machine with another one and/or change the 
> ethernet address of the satellite, is there any way to modify the 
> existing satellite, or is it better/easier/the only option to set up a 
> completely "new" satellite?

   If you do a completely "new" satellite, don't forget to remove the old 
   setup.

   Changing the ethernet address can be done, but is not documented.  You 
   have to change the MOP databases on all servers that can serve the MOP 
   request to recognize the new address.  Then look for any other 
   dependencies, such as page/swap disk volume names to see if they need to 
   be updated.

   If the new satellite is different hardware from the old, you may find
   that the saved SYSGEN parameters from the old system prevent
   successfull boot, or make it painfully slow.