A few applications for some of this thought.
1) I have long lusted after something Like MC/ServiceGuard on Linux.
My favorite setup is one EMC RAID box being shared by two HP-UX systems,
inter-connected with MC\ServiceGuard. Running thin-server Oracle makes
this a sweet deal. Two of these with Oracle parallel-server cannot be
crashed easily.
2) Networked RAID1 could eliminate the need for rdist in many
environments.
> [mailto:[EMAIL PROTECTED]]On Behalf Of Alvin Oga
> Sent: Monday, October 04, 1999 6:29 PM
>
> hi ya tom
>
> if the idea is to have a "fail safe" system....
>
> when we were doing doa work for the gov't... we had to have
> multiple redundancy....and redundancy for the redundancy...
> ( gov't had too much $$$ to throw at it )
>
> but basically, how I would like to see a "HA" type linux system
> would have:
> dual-port scsi controller... read/write by two different servers
> -
> - this is the key factor...in my mind...
> -
>
> dual CPU is nice...but it's worthless(?)...
> - many other points of failures...
> ( mb, cpu, memory, disk, connector, cables,
> power supp, electricity, etc )
>
> you really want two motherboards and/or boxes that access
> the same disk... if one system fails...the other system
> should be able to read/write that data..
>
> - if one "system" fails...
> than the other "system" can step in...
> ( multi-host servers....www1, www2, www3 acting as "www"
> ( for now sun boxes does this better than linux ? )
>
> when there is a transaction like a mc/visa/amex transaction occur...
> the terminal sends that request to two servers... both record the
> request... one of the two machines will respond with the
> authorization...
> and they both acknowledge that the task was done...
> - if it's not acknowledged... the task is pending still cause
> the other system got stuck someplace...
>
> well...guess i just wanted to say that...."dual-port disk controller"
> is what does the job best...if not... the disk contoller dies and all
> hell breaks loose... or the motherboard dies and ..so on...
>
> ( my adaptec controller just died this past week...so it's an issue )
> - no monthly tape archive for a while...
>
> have fun
> alvin
>
> > Tom Kunz wrote:
> >
> > SW-RAID List,
> > This is slightly off-topic. No, in fact it might be
> further than just
> > "slightly". I have been exploring redundant network filesystems for
> > Linux, off and on for the past several months. I need
> something that
> > will replicate a fs across a lan, much the same way RAID-1
> duplicates
> > fs's. The purpose is for a high-availability system, where several
> > nodes participate to keep a set of services active indefinitely. My
> > company uses a SCO solution, called "Sentinel", which is just a
> > single-master/single-slave arrangement that duplicates
> disks between two
> > machines. When the master node goes down, the other
> assumes its IP, and
> > has an identical filesystem as the dead machine. When the
> master comes
> > back up, it resyncs to the master and assumes the slave
> position again.
> > But we want to dump SCO and go entirely with Linux, and
> have the same
> > functionality.
> > I have already explored Coda, InterMezzo, and the
> Linux-HA website
> > (http://www.henge.com/~alanr/ha). So far, the HA site only
> has the IP
> > assumption source, and links to other sites I've already
> taken a look
> > at, none of which contain what I think is necessary for a redundant
> > network filesystem. Coda and InterMezzo seem more like "caching"
> > solutions, for mobile or remote computing, not as a *redundant*,
> > fully-duplicated filesystem. I attended a seminar at LinuxExpo in
> > Raleigh, NC on GFS, but that looked like something still in
> its infancy,
> > and relying somewhat heavily upon certain SCSI and Fiber-Channel
> > features. I want something that anyone with >1 machine and any
> > linux-supported disk media can use as RAID-1 data duplication.
> > After considering the RAID-1 code that has come to
> (relative) maturity
> > here, it seems like a good code base to get started on a networked
> > RAID-1-type system. Basically, rather than sync-ing between two
> > physically local disks, modify the code to sync between a
> local and a
> > remote (or more than one remote) disk. Maybe I've missed something
> > about Coda, GFS, or Intermezzo, or maybe there's an
> entirely different
> > system that already does exactly what I want (as open-source, of
> > course). But if not, is there anyone else on this list who is
> > interested in venturing out into this arena?
> > Thanks,
> > Tom
> >
> > --
> > Tom Kunz Tool Developer Software Consulting Services
> > PGP Key http://www.users.fast.net/~tkunz/pgp.html
> > 1452 1F99 E2BB 632E 6EAE 2DF0 EF11 4DFC
> > DB62 7EBC 3BA0 6C40 88C0 C509 DA85 91B4 D5E9 EFD3
> >
>
