Hi,
As promised a summary regarding using ADSM to backup UNIX Systems.
As normal, thanks to all who replied.
Mike
------- Forwarded Messages
> Mike !
>
> I dont use ADSM.
> But if your primaly goal is to backup UNIX systems,
> then my rekomendation would be Legatos Networker.
> And to use DLT tape stations.
>
> I have a small mixed environment here.
> My server is a DU server A2100 with a TZ887 tape station.
> My klients are:
>
> NT both INTEL and ALPHA
> SUN SOLARIS
> IBM AIX
> SGI
>
> It works real well.
> It has extra addons for databases etc.
> (i dont use them today)
>
> Regard
>
> Martin
>
------- Message 2
> Hi Mike,
> We loaded the ADSM client (v2.0) onto an Alpha 2000 running Digital UNI
X
> 3.2G around three weeks ago. It holds around 80GB of data on UFS filesystems.
> Initial tests are extremely promising. Previously we were backing up to DLT
> Tape. Individual file restores could take up to 40 minutes. They now take aro
und
> 3 minutes.
> The only word of caution...we still require copies of the root and usr partit
ion
> on tape for disaster recovery as the ADSM client needs to be loaded on a
> skeleton operating system before a restoration can take place.
>
> Hope this helps,
>
> David Shaw
> Systems Administrator
> United Energy
> Australia.
>
> Mike D Cross:
> >Hi,
> >
> >We are looking at installing an Enterprise backup solution and our
> >consultant has recommended ADSM from IBM. On paper it appears
> >to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> >but the spec etc does not give any indication of its use in real
> >life.
> >
> >What I'd really like to know is:
> >1) Is anyone using ADSM to back up unix?
> >2) How big is the installation and what kind of server do you have
> >3) how does the system fair when all is going well
> >4) what tends to go wrong and how much pain is it to fix.
> >
> >Thanks in advance.
> >
> >Mike
> >
> >P.S. Expect a Summary in 7 days time.
> >
> >
> >=======================================================================
> >Mike Cross
> >Principal Analyst
> >UNIX Systems
> >SmithKline Beecham Phone: +44 (0)1279-644858
> >New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> >Third Avenue, Harlow,
> >CM19 5AW email: crossmd_at_sbphrd.com
> >
>
------- Message 3
> On Fri, 22 May 1998, Mike D Cross wrote:
>
> > Hi,
> >
> > We are looking at installing an Enterprise backup solution and our
> > consultant has recommended ADSM from IBM. On paper it appears
> > to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> > but the spec etc does not give any indication of its use in real
> > life.
> >
> > What I'd really like to know is:
> > 1) Is anyone using ADSM to back up unix?
>
> We use ADSM to back up our Aix's, Du's and Linux. Also for Wintel and macs.
>
> > 2) How big is the installation and what kind of server do you have
>
> About a dozen Unix. Mostly Digital but also aix, sun and Linux. Some
> are work stations some are large servers. The server is current running
> on an IBB mainframe running VM. It will be migrating to either MVS or
> AIX in the near future.
>
> > 3) how does the system fair when all is going well
>
> We run the system in schedule mode and the big problem is that every body
> gets so used to not having to worry about backups that they fail to check
> the logs to see if every thing went all right. Some day I will get
> around to automating that.
>
> > 4) what tends to go wrong and how much pain is it to fix.
>
> Our biggest problem is running out of tapes in the storage pool.
>
> For downside bare iron restores are not easy. Fortunately my critical
> servers are all on hot swapable disk and I can restore one system disk by
> using another server.
>
> Without co-location data is really spread out over a lot of tapes. A
> complete restore of a large file system is not pretty. On the other hand
> it is great for user restores of one or two files at a time. Sort of
> depends on the way you look at the backup. Is it for disater recovery or
> is it for user oops. This system seems to be a good compromise. In fact
> it is the only IBM product I use that I really would not want to do without.
>
> We have been running it since it was called WDSF.
>
>
> >
> > Thanks in advance.
> >
> > Mike
> >
> > P.S. Expect a Summary in 7 days time.
> >
> >
> > =======================================================================
> >
>
> David E. Tetreault davet_at_uriacc.uri.edu
> Manager of Technical Support 401-874-4472
> OIS/TOPS, Tyler Hall
> University of Rhode Island
> Kingston RI 02881
>
>
------- Message 4
> Mike,
>
> 1) we are using ADSM to backup our 15 AlphaServer (DU 3.2D and 4.0B) running
> SAP R/3 and Oracle Databases.
> 2) Unfortunately, I can't speak for the server part of the installation. I'm
a
> Unix admin and have no idea what the MVS guys are doing.
> We have two Magstar tape roboter connected to the IBM MVS host and aprox. 3 T
B
> of capacity.
> >From the UNIX point of view it is a black box. We schedule the backups with
> cron and restore files with a GUI.
> 3) We are quite pleased with our installation - you never have to worry about
> tapes anymore. Backup is fast enough (30 GB aprox. 200 mins)
> 4) not much trouble, can't remember anything important.
>
> If you have some specific questions I'll try to find out.
>
> Greetings
> Peter
>
> Peter Braack
> Unix System Administrator
> Degussa AG Frankfurt / Germany
> Peter.Braack_at_degussa.de
>
>
>
>
>
> alpha-osf-managers-owner_at_ornl.gov am 22.05.98 09:40:00
> An: alpha-osf-managers_at_ornl.gov _at_ INTERNET
> Kopie: crossmd_at_heu534.ha.uk.sbphrd.com _at_ INTERNET
> Thema: Anyone using ADSM to backup UNIX systems.
>
> Hi,
>
> We are looking at installing an Enterprise backup solution and our
> consultant has recommended ADSM from IBM. On paper it appears
> to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> but the spec etc does not give any indication of its use in real
> life.
>
> What I'd really like to know is:
> 1) Is anyone using ADSM to back up unix?
> 2) How big is the installation and what kind of server do you have
> 3) how does the system fair when all is going well
> 4) what tends to go wrong and how much pain is it to fix.
>
> Thanks in advance.
>
> Mike
>
> P.S. Expect a Summary in 7 days time.
>
>
> =======================================================================
> Mike Cross
> Principal Analyst
> UNIX Systems
> SmithKline Beecham Phone: +44 (0)1279-644858
> New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> Third Avenue, Harlow,
> CM19 5AW email: crossmd_at_sbphrd.com
>
>
>
------- Message 5
> We take care of some mid-range systems (AIX, HP-UX, Sun OS, and Digital
> Unix). We have an ADSM server (on an RS 6000), and clients on all
> mid-range boxes that we're responsible for and our desk-top PCs (Windows
> 95 and NT), too. These number approximately in the hundreds. Other parts
> of MCI that I'm familiar with also use ADSM.
>
> Both our server and most of our clients are version 2 release 1 (various
> levels). A few of our DU boxes have a newer client, version 3, release 1,
> level 0.3.
>
> When everything's going well, it's all transparent to the users (us and
> our [MCI internal] clients). Occasionally someone needs something back,
> and the clients (with both a command-line interface and a GUI) do just
> fine, especially the newer version 3 client GUI. We've even used it to
> bring back entire file systems, with no trouble.
>
> Even when we have trouble with ADSM, it's something minor like needing
> to re-configure the client after an OS upgrade (there's more than one
> way to have the client do its thing).
>
> Hugh
> Hugh Pritchard, M.Sc.
> Mailto: Hugh.Pritchard_at_MCI.com
> Washington, DC, area
>
------- Message 6
> You wrote:
>
> >Hi,
> >
> >We are looking at installing an Enterprise backup solution and our
> >consultant has recommended ADSM from IBM. On paper it appears
> >to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> >but the spec etc does not give any indication of its use in real
> >life.
> >
> >What I'd really like to know is:
> >1) Is anyone using ADSM to back up unix?
>
> Yah, we dump a 60Gb SSA array on to an ADIC 458 robot w/ 3 DLT IV 4000
> tape drives w/ ADSM.
>
> >2) How big is the installation and what kind of server do you have
>
> Roughly 80 megs on an IBM RS/6000 model 3CT.
>
> >3) how does the system fair when all is going well
> >4) what tends to go wrong and how much pain is it to fix.
>
> I can't say much about these two. We've only been using it for a few
> months.
>
> ADSM blows on AIX (and AIX pretty much sucks itself). IMHO, amanda
> (www.amanda.org), is much better, is free, and comes w/ source code in
> case it breaks. At the University of Maryland, we use amanda in three
> different installations to back up roughly 500 workstations. In the
> UMIACS parallel lab alone, we've been backing up >344GB of data on a
> DEC TL820 tape library without many problems (and none serious).
>
> --
> Gary Jackson
> bargle_at_umiacs.umd.edu
>
------- Message 8
> I'm not using ADSM on Digital UNIX now, but I did use it on my previous
> job. I had several AIX system clients backing up to our MVS mainframe
> tape storage towers every night via standard ethernet TCP-IP. We
> probably pushed about 10-12 GB a week, without any hitches.
>
> ADSM is *very* *very* cool for single file and subdirectory restorals,
> but on filesystem restorations it was a total dog. One co-worker needed
> 8 hours to restore his entire root filesystem from ADSM.
>
> I recommend that you use ADSM for nightly backups of all your
> "non-system" files -- like /home and application data areas, /var,
> critical config files in /etc, and others.
>
> Personally, no matter what enterprise solution you choose, I'd still
> running at least one weekly tape backup. Tape is always the failsafe. :)
> (The tapes were even more important on AIX because you could build
> bootable tape backups for disaster recovery purposes... ADSM doesn't let
> you have that same kind of functionality.)
>
> One other thing about ADSM is that the command syntax is kind of
> cryptic. At least, I had that feeling since I've worked mainly with UNIX
> in my professional career. The command line client had a distinctly
> MVS/VMS feel to it, which irritated me. Regular expressions, for
> example, don't exist in any sophisticated form on ADSM.
>
> Overall, I like the product, but in my opinion some level of tape backup
> will still be required.
>
> --
> Mark Allen -- 415-995-3726 -- Mark.Allen_at_pbdir.com
> UNIX System Administrator -- Pager/PCS 510-599-7893
> Pacific Bell Directory
>
> > -----Original Message-----
> > From: Mike D Cross [SMTP:crossmd_at_mh.uk.sbphrd.com]
> > Sent: Thursday, May 21, 1998 11:39 PM
> > To: alpha-osf-managers_at_ornl.gov
> > Cc: crossmd_at_heu534.ha.uk.sbphrd.com
> > Subject: Anyone using ADSM to backup UNIX systems.
> >
> > Hi,
> >
> > We are looking at installing an Enterprise backup solution and our
> > consultant has recommended ADSM from IBM. On paper it appears
> > to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> > but the spec etc does not give any indication of its use in real
> > life.
> >
> > What I'd really like to know is:
> > 1) Is anyone using ADSM to back up unix?
> > 2) How big is the installation and what kind of server do you have
> > 3) how does the system fair when all is going well
> > 4) what tends to go wrong and how much pain is it to fix.
> >
> > Thanks in advance.
> >
> > Mike
> >
> > P.S. Expect a Summary in 7 days time.
> >
> >
> > ======================================================================
> > =
> > Mike Cross
> > Principal Analyst
> > UNIX Systems
> > SmithKline Beecham Phone: +44 (0)1279-644858
> > New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> > Third Avenue, Harlow,
> > CM19 5AW email: crossmd_at_sbphrd.com
>
------- Message 9
> I don't know if our experiences with ADSM will help you but here they are.
>
> We were using ADSM to backup OS/2, AIX, and Solaris to an IBM MVS
> mainframe. Everything worked well except that our Unix backups were
> loading down the MVS system and out IS department requested us to do the
> backups off ours. Since that didn't meet our needs, we have since
> switched to Legato Networker. We experienced very few problems with ADSM
> and used it for complete system restorations in many cases. We did have
> some initial problems with the Solaris client failing but they were
> corrected quickly. Hope this helps.
>
> On Fri, 22 May 1998, Mike D Cross wrote:
>
> > Hi,
> >
> > We are looking at installing an Enterprise backup solution and our
> > consultant has recommended ADSM from IBM. On paper it appears
> > to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> > but the spec etc does not give any indication of its use in real
> > life.
> >
> > What I'd really like to know is:
> > 1) Is anyone using ADSM to back up unix?
> > 2) How big is the installation and what kind of server do you have
> > 3) how does the system fair when all is going well
> > 4) what tends to go wrong and how much pain is it to fix.
> >
> > Thanks in advance.
> >
> > Mike
> >
> > P.S. Expect a Summary in 7 days time.
> >
> >
> > =======================================================================
> > Mike Cross
> > Principal Analyst
> > UNIX Systems
> > SmithKline Beecham Phone: +44 (0)1279-644858
> > New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> > Third Avenue, Harlow,
> > CM19 5AW email: crossmd_at_sbphrd.com
> >
> >
>
> *------------------------------------------------------------------------*
> | The foregoing represents the opinion of the sender ,,, |
> | and not necessarily that of the company. (. .) |
> +---------------------------------+-----------------------oOO--(_)--OOo--|
> | Bill Kamps, Principal Engineer | email: wdkamps_at_srp.gov |
> | Salt River Project +--------------------------------------+
> | Mailstop POB006 | (602) 236-3922 |
> | P.O. Box 52025 | (602) 236-4327 fax |
> | Phoenix, AZ 85072-2025 | (602) 275-2508 # 7395 pager |
> +---------------------------------+--------------------------------------+
> | Normal Hours: 8:30 am - 7:00 pm MST, Tuesday through Friday |
> *------------------------------------------------------------------------*
>
>
------- Message 10
> Hi,
>
> We are looking at installing an enterprise unix backup solution,
> our consultant has recommended IBM's ADSM. On paper this looks like
> a good choice as it covers all the unix platforms we have, but before
> going any further I'd really like to know:
>
> 1) who is using adsm to backup unix.
> 2) how big is the environment and the server
> 3) how it operates when all is going ok
> 4) what goes wrong with adsm and how easy is it to fix it afterwards.
>
> Thanks in advance
>
> Mike
>
>
> =======================================================================
> Mike Cross
> Principal Analyst
> UNIX Systems
> SmithKline Beecham Phone: +44 (0)1279-644858
> New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> Third Avenue, Harlow,
> CM19 5AW email: crossmd_at_sbphrd.com
------- Message 11
>
> --------------10A33B6B0007E1B47CEA02D6
> Content-Type: text/plain; charset=us-ascii
> Content-Transfer-Encoding: 7bit
>
> Hi Mike,
>
> I'm using ADSM to backup 6 UNIX servers (as far as I now UNIX is the
> primary platform for ADSM, at least new releases arrive first on UNIX) and
> few NT's as well. We also use it for archiving, HSM and it is a central
> item in our disaster recovery planning. The ADSM server hardware is a
> RS/6000 43P, with 128MB, 18 GB of disks and a Magstar 3570 Tape Library
> (very fast one). This answers 1) and 2)
>
> 3) and 4)
> So far ADSM has faired very well, we haven't experienced any problems. It
> is very efficient system due to it's performance and incremental forever
> methodology (we use only 1/3 of the tapes with ADSM, compared to what we
> did earlier).
>
> Kind regards,
> Helgi Viggosson.
>
> Mike D Cross wrote:
>
> > Hi,
> >
> > We are looking at installing an Enterprise backup solution and our
> > consultant has recommended ADSM from IBM. On paper it appears
> > to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> > but the spec etc does not give any indication of its use in real
> > life.
> >
> > What I'd really like to know is:
> > 1) Is anyone using ADSM to back up unix?
> > 2) How big is the installation and what kind of server do you have
> > 3) how does the system fair when all is going well
> > 4) what tends to go wrong and how much pain is it to fix.
> >
> > Thanks in advance.
> >
> > Mike
> >
> > P.S. Expect a Summary in 7 days time.
> >
> > =======================================================================
> > Mike Cross
> > Principal Analyst
> > UNIX Systems
> > SmithKline Beecham Phone: +44 (0)1279-644858
> > New Frontiers Science Park (South) Fax: +44 (0)1279-644969
> > Third Avenue, Harlow,
> > CM19 5AW email: crossmd_at_sbphrd.com
>
>
>
> --
> -------------------------------------------------------------
> Helgi Viggosson, Sr. Software Eng. ||
> Nyherji hf || mailto:helgiv_at_itn.is
> Skaftahlid 24, || http://www.nyherji.is
> 105 Reykjavik, || Tel +354 569 7700
> Iceland || Fax +354 569 7799
> -------------------------------------------------------------
>
>
>
> --------------10A33B6B0007E1B47CEA02D6
> Content-Type: text/html; charset=us-ascii
> Content-Transfer-Encoding: 7bit
>
> <HTML>
> Hi Mike,
>
> <P>I'm using ADSM to backup 6 UNIX servers (as far as I now UNIX is
> the primary platform for ADSM, at least new releases arrive first on UNIX)
> and few NT's as well. We also use it for archiving, HSM and
> it is a central item in our disaster recovery planning. The ADSM s
erver
> hardware is a RS/6000 43P, with 128MB, 18 GB of disks and a Magstar 3570
> Tape Library (very fast one). This answers 1) and 2)
>
> <P>3) and 4)
> <BR>So far ADSM has faired very well, we haven't experienced any problems.&nb
sp;
> It is very efficient system due to it's performance and incremental forever
> methodology (we use only 1/3 of the tapes with ADSM, compared to
> what we did earlier).
>
> <P>Kind regards,
> <BR>Helgi Viggosson.
>
> <P>Mike D Cross wrote:
> <BLOCKQUOTE TYPE=CITE>Hi,
>
> <P>We are looking at installing an Enterprise backup solution and our
> <BR>consultant has recommended ADSM from IBM. On paper it appears
> <BR>to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> <BR>but the spec etc does not give any indication of its use in real
> <BR>life.
>
> <P>What I'd really like to know is:
> <BR>1) Is anyone using ADSM to back up unix?
> <BR>2) How big is the installation and what kind of server do you have
> <BR>3) how does the system fair when all is going well
> <BR>4) what tends to go wrong and how much pain is it to fix.
>
> <P>Thanks in advance.
>
> <P>Mike
>
> <P>P.S. Expect a Summary in 7 days time.
>
> <P>=======================================================================
> <BR>Mike Cross
> <BR>Principal Analyst
> <BR>UNIX Systems
> <BR>SmithKline Beecham &
nbsp;
> Phone: +44 (0)1279-644858
> <BR>New Frontiers Science Park (South) Fax: +44 (0)1279-644
969
> <BR>Third Avenue, Harlow,
> <BR>CM19 5AW  
;
> email: crossmd_at_sbphrd.com</BLOCKQUOTE>
>
> <PRE>--
> -------------------------------------------------------------
> Helgi Viggosson, Sr. Software Eng. ||
> Nyherji hf &
nbsp; &n
bsp; || <A HREF="mailto:helgiv_at_itn.is">mailto:helgiv_at_itn.is</A>
> Skaftahlid 24, &nb
sp; || <A HREF="htt
p://www.nyherji.is">
http://www.nyherji.is</A>
> 105 Reykjavik, &nb
sp; || Tel +354 569
7700
> Iceland &nbs
p;  
; || Fax +354 569 7799
> -------------------------------------------------------------</PRE>
> </HTML>
>
> --------------10A33B6B0007E1B47CEA02D6--
>
>
------- Message 12
> > We are looking at installing an Enterprise backup solution and our
> > consultant has recommended ADSM from IBM. On paper it appears
> > to support all the UNIX platforms we need (DU/IRIX/Solaris/HP-UX)
> > but the spec etc does not give any indication of its use in real
> > life.
> >
> > What I'd really like to know is:
> > 1) Is anyone using ADSM to back up unix?
> > 2) How big is the installation and what kind of server do you have
> > 3) how does the system fair when all is going well
> > 4) what tends to go wrong and how much pain is it to fix.
> >
> Enterprise backup is a big problem, with no trivial solution.
>
> First off you need to define backup. What is "backup" and why are you doing
> it?
>
> We define backup as "platform level disaster recovery."
> "Backup" is NOT archival storage.
> (And don't let anybody tell you that HSM has any part of a backup philosophy.
)
>
> These are two distintly different problems.
>
> We backup 27 servers - 22 DU boxes, 2 Suns and 3 Macs using Digital's
> NSR. (Aka LEGATO) We have an MTI 28 tape jukebox and a 100meg independent
> backup network. (2 network interfaces per server.) The backup server ia a
> 1000A, but it doesn't really do anything ... it's idle 97% of the time,
> even when it is actively running a backup.
>
> Backup is trival and works flawsly - recovery on the other hand is a
> real disaster.
>
> Basically, we have gotten to the size where many of our platforms can no
> longer be recovered from tape.
>
> Why? Because it takes too long!!!!
>
> This means that for disaster recovery - ie disk crashes - we must use
> a RAID structure.
>
> We lost the disk controller on a mail server 2 weeks ago and trashed
> part of the raid set as a result. It is a relatively small data structure -
> 6 gig 0+1 raid array. The quick summary - we were able to disk-to-disk copy
> all but 6 userids from the RAID array hours faster than we were able to
> re-build the RAID-set from tape.
>
> One tape drive per system is still faster on recovery than virtually any
> setup which consolidates (ie streams) multiple hosts into a single tape.
> But a DLT7000 per system can be expensive as well as a pain in the ass for
> tape management.
>
> Again, this is a big problem, and the killer will not be doing the actual
> backups, but using those backups to recover a system.
>
> By the way - we use NSR because our mainframe folks (who run ADSM) can't
> deal with all of the complexities of network computing. It can take them
> weeks of trial and error to add a single workstation to their backup cycle.
> And there is no way they could handle the 6-20 gig we have per server.
> ADSM runs on the IBM-3090.T.T.F.N.
>
> I could go on and on.... let me know if you have any other questions.
>
> ===========<cut here>============
> University Intramural Correspondence
> Data Communications and Computing Services
>
>
> To: DCCS Computing Services
> From: William H. Magill, Manager, DCCS Computing Services
> Date: 24 September 1993
>
> Subject: DCCS Backup policy
>
> BACKUP is performed daily (on University working days) on a SYSTEM level
> for the purpose of restoration of service in the event of catastrophic
> loss.
>
> DCCS MAKES NO PROVISION FOR THE RETRIEVAL OR RESTORATION OF INDIVIDUAL
> FILES OR MESSAGES.
>
> The PRIMARY purpose of doing BACKUP is to maintain SYSTEM integrity. That
> is, to provide the ability to recreate the SYSTEM as of some point in time
> following the event of a catastrophic disk loss, such as a disk head crash.
> Backup is oriented toward the preservation and restoration of the contents
> of PHYSICAL volumes of data, not individual files.
>
> Although an incidental capability of BACKUP allows the recovery individual
> files lost by individual users, DCCS does not offer such a service.
>
> BACKUP is NOT an archival storage, nor an "off-line" storage mechanism, for
> users.
>
> NO MECHANISM EXISTS FOR THE BACKUP OF INDIVIDUAL USER FILES. If such a
> backup is desired it is incumbent upon the individual user to transfer
> those files to some other system where they can personally perform a
> personal backup.
>
> BACKUP is the complete, systematic and regular copying to tape of all files
> and file system volumes so one is able to restore volumes in the shortest
> amount of time .
>
> While it may sound reasonable to attempt to save tape by omitting the
> backup of certain files with low modification rates, such as application
> packages, the operating system and the like, since you can always reload
> them from the release tapes or an older backup, you loose the time by
> having to process multiple tapes, assuming that you remember and can even
> find the correct tapes. This is especially a problem if the "released"
> software must be "configured" first before it can be used. Tape is
> incredibly cheap compared to the amount of time/money expended by the
> consumption of a system administrator's time reconstructing a system from
> parts when a simple reload can be accomplished by an operator.
>
> To assure the integrity of certain data structures, BACKUP must be done in
> a stand-alone environment. This is because BACKUP is a process which
> extends forward in time, and is NOT an instantaneous snapshot as we might
> desire. Depending upon the applications involved such a concern may or may
> not be relevant.
>
> Stand-alone BACKUP is NOT done for DCCS Unix systems , as this conflicts
> with their being available 24 hours a day 7 days a week, non-stop.
>
> Therefore, other measures must be taken by some applications to assure
> appropriate recovery information exists.
>
> Ingres is a case in point. Ingres "checkpoint files" are taken at periodic
> intervals prior to the normal BACKUP run. Since these files are closed at
> the time BACKUP is begun and remain closed and unmodified until BACKUP is
> completed they permit the recovery of an Ingres database by means of
> standard, Ingres provided, recovery procedures.
>
> Most DCCS Unix based systems and application have simple, sequential, flat
> file structures. Consequently, on most DCCS Unix based systems the nature
> of the applications are such that a relatively quiescent time period may be
> used for purposes of BACKUP. When performed in this manner, we have a high,
> but not absolute, probability of obtaining a complete and coherent
> snapshot of a given file system volume.
>
> To this end, BACKUP on the DCCS Unix systems takes place in the time period
> between midnight and 8 am.
>
> BACKUP only attempts to maintain a picture of the files PRESENT on the
> system at the time of the LAST backup. Therefore, since backup is normally
> performed in the period between 2am and 6am, it is possible for an
> individual to loose an entire day's mail traffic.
>
> Unix backup tapes are cycled on a bi-weekly basis. Each tape contains a
> level zero (total) backup of the normally mounted file systems. Ten tapes
> are used in the cycle. Hence every 10 backups each tape is overwritten.
> BACKUP on the Unix systems is done to 8mm ExaByte 8500 tape drives capable
> of containing 5 MB of data. No backup is performed on the weekend nor over
> University Holidays.
>
>
>
>
>
> William H. Magill Senior Systems Administrator
> Information Services and Computing (ISC) University of Pennsylvania
> Internet: magill_at_isc.upenn.edu magill_at_acm.org
> magill_at_upenn.edu http://pobox.upenn.edu/~magill/
>
------- End of Forwarded Messages
Received on Tue Jun 23 1998 - 08:47:50 NZST