ontape vs. onbar
Hi.
I'm looking for some pros and cons about ontape vs. onbar. I'm running
7.24.UC6 on AIX 4.2.1. We now use ontape. We are now looking to change to
onbar but I want to know if the are any drawbacks. Also any thoughts on ISM
vs. IBM ADSM.
Thanks for any comments.
-----------== Posted via Deja News, The Discussion Network ==----------
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We are currently using both ontape and OnBar/ADSM. We intend to switch
completely to OnBar once we have the opportunity to perform a disaster
recovery test w/Comdisco using OnBar/ADSM. From my viewpoint, OnBar is
superior because:
1) It keeps the logs and backups separate (ontape backup includes the
latest log on the backup tape, from what I can tell). So I can still
restore to current time if I lose a backup, as long as I have an earlier
backup and all logs since then.
2) OnBar can backup dataspaces concurrently. This can reduce your backup
time depending upon the load your servers can handle.
3) Most storage managers that OnBar interfaces with (definitely ADSM and
probably ISM) label tape volumes and do not allow inadvertent overwrites (as
long as you only access the tapes with the storage manager). Ontape will
write to the tape.. PERIOD.
4) an OnBar restore will automatically grab the latest level-0 backup,
restore it, grab the latest level-1 backup, restore it, etc and then apply
all applicable logs. So restore is MUCH more automated and assured (not to
mention simpler)
5) OnBar keeps track of backups and logs, so you don't have to.
On the negative side,
1) OnBar is more difficult to restore a database from one server to another
server that contained a database already. Can be done, you just have to
step through several hoops (particularly with ADSM )
2) You have more setup to perform with OnBar than ontape. But then, you
get more functionality from OnBar, so that's a trade-off.
As far as ADSM vs ISM, I prefer ADSM because:
1) ADSM addresses all backups, not just Informix database. I use ADSM to
backup my data filesystems on my Unix systems as well as use it to store
Informix backups
2) ADSM provides a central location for all backups (the ADSM server),
while ISM covers only the local machine. With half a dozen database
servers, that simplifies my operating procedures.
3) Coming from a mainframe history (MVS, IMS, DB2, etc.), I've still got a
little blue blood.
Other than that, ADSM and ISM seem to provide the same services for OnBar.
Just my opinions, not necessarily valid, and certainly humble and open to
correction.
Doug Agnew
DBA
Charlotte Pipe & Foundry
dagnew@charlottepipe.com
david_dd@my-dejanews.com wrote in message
<7g2e7f$umf$1@nnrp1.dejanews.com>...
>Hi.
>
>I'm looking for some pros and cons about ontape vs. onbar. I'm running
>7.24.UC6 on AIX 4.2.1. We now use ontape. We are now looking to change to
>onbar but I want to know if the are any drawbacks. Also any thoughts on
ISM
>vs. IBM ADSM.
>
>Thanks for any comments.
>
>-----------== Posted via Deja News, The Discussion Network ==----------
>http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Just some minor comments on Doug's reply:
Doug Agnew wrote:
>
> We are currently using both ontape and OnBar/ADSM. We intend to switch
> completely to OnBar once we have the opportunity to perform a disaster
> recovery test w/Comdisco using OnBar/ADSM. From my viewpoint, OnBar is
> superior because:
> 1) It keeps the logs and backups separate (ontape backup includes the
> latest log on the backup tape, from what I can tell). So I can still
> restore to current time if I lose a backup, as long as I have an earlier
> backup and all logs since then.
You can elect to not back up the current log in ontape.
> 2) OnBar can backup dataspaces concurrently. This can reduce your backup
> time depending upon the load your servers can handle.
> 3) Most storage managers that OnBar interfaces with (definitely ADSM and
> probably ISM) label tape volumes and do not allow inadvertent overwrites (as
> long as you only access the tapes with the storage manager). Ontape will
> write to the tape.. PERIOD.
Except it will not overwrite an earlier tapeset from the same archive
set so it you accidentally remount set #1 instead of set #3 it will
reprompt.
> 4) an OnBar restore will automatically grab the latest level-0 backup,
> restore it, grab the latest level-1 backup, restore it, etc and then apply
> all applicable logs. So restore is MUCH more automated and assured (not to
> mention simpler)
> 5) OnBar keeps track of backups and logs, so you don't have to.
To the plusses let me add:
o Onbar, through the storage manager (ie ISM, ADSM, Legato, etc)
supports multiple simultaneous use of several tape devices.
o Onbar permits point in time recovery. Ontape only supports logical
log archive granularity of restores. Depending on how you are backing
up your logical logs (ie using the alarm program) you can simulate
point in time recover at the single log level.
> On the negative side,
> 1) OnBar is more difficult to restore a database from one server to another
> server that contained a database already. Can be done, you just have to
> step through several hoops (particularly with ADSM )
> 2) You have more setup to perform with OnBar than ontape. But then, you
> get more functionality from OnBar, so that's a trade-off.
> As far as ADSM vs ISM, I prefer ADSM because:
> 1) ADSM addresses all backups, not just Informix database. I use ADSM to
> backup my data filesystems on my Unix systems as well as use it to store
> Informix backups
> 2) ADSM provides a central location for all backups (the ADSM server),
> while ISM covers only the local machine. With half a dozen database
> servers, that simplifies my operating procedures.
> 3) Coming from a mainframe history (MVS, IMS, DB2, etc.), I've still got a
> little blue blood.
>
> Other than that, ADSM and ISM seem to provide the same services for OnBar.
>
> Just my opinions, not necessarily valid, and certainly humble and open to
> correction.
>
> Doug Agnew
> DBA
> Charlotte Pipe & Foundry
> dagnew@charlottepipe.com
> david_dd@my-dejanews.com wrote in message
> <7g2e7f$umf$1@nnrp1.dejanews.com>...
> >Hi.
> >
> >I'm looking for some pros and cons about ontape vs. onbar. I'm running
> >7.24.UC6 on AIX 4.2.1. We now use ontape. We are now looking to change to
> >onbar but I want to know if the are any drawbacks. Also any thoughts on
> ISM
> >vs. IBM ADSM.
> >
> >Thanks for any comments.
> >
> >-----------== Posted via Deja News, The Discussion Network ==----------
> >http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own