Is it possible to have two Instances of 7.5.1 on one box

DS4DRIVER · Post by **DS4DRIVER** » Tue Jan 03, 2006 10:22 am

Hi,
Is it possible to have two instances of DataStage Server 7.5.1 installed on the same box.

Thanks

ArndW · Post by **ArndW** » Tue Jan 03, 2006 10:46 am

Yes, it is possible. The procedure to do so is documented in the installation manual and a search of this site will also show some threads on the subject.

ray.wurlod · Post by **ray.wurlod** » Tue Jan 03, 2006 4:01 pm

Search for "-itag"

DS4DRIVER · Post by **DS4DRIVER** » Wed Jan 04, 2006 8:21 am

Currently the .dshome is ponting to the existing instance's Home directory.
Also, the dsenv file uses this home directory.
For the new Instance, what are the necessary things that i need to take care of before moving forward.

Unfortunately, the Installation document does not say about these things.

Thanks

ArndW · Post by **ArndW** » Wed Jan 04, 2006 8:57 am

Each instance will have it's own path to the home directory; the /.dshome entry will only be valid for one of your instances, the other one(s) need to be attached to directly. Similarly you will have to append a port number when connecting to a second instance from any one of the 4 client programs, since they listen on different port numbers. I am fairly certain that the documentation discusses this, but please post if it leaves other questions open.

DS4DRIVER · Post by **DS4DRIVER** » Wed Jan 04, 2006 9:20 am

This is a part of dsenv file for the existing instance.
Do you think i should comment the first if block (anyway, the second if block overrides the DSHOME value)

if [ -z "$DSHOME" ] && [ -f "/.dshome" ]
then
DSHOME=`cat /.dshome`
export DSHOME
fi

if [ -z "$DSHOME" ]
then
DSHOME=/opt/DataStage/Ascential/DataStage/DSEngine; export DSHOME
fi

Thanks

ArndW · Post by **ArndW** » Wed Jan 04, 2006 9:49 am

No, don't change the existing instance; there is no reason to do so, the /.dshome will continue to point to this instance. The 2nd and further instances are those that have a different path. Just make sure that $DSHOME is set to the appropriate path for your session's requested instance.

DS4DRIVER · Post by **DS4DRIVER** » Wed Jan 04, 2006 12:51 pm

The Network Admin has created a Logical Host on the server that currently runs DS 7.5.1. I am planning to install the new instance on this Logical node. Is it possiple to install DS server with out the -itag option.

Thanks

ArndW · Post by **ArndW** » Wed Jan 04, 2006 12:59 pm

If the "logical host" is a distinct machine, with it's own IP address and nodename and it's own instance of UNIX then it should work. Basically the DataStage engine will use a reserved block of shared memory and communication ports, so if you wish multiple instances on the same machine you need to differentiate these. If you have another virtual machine then this is hidden from DataStage, which sees only "it's" environment. I've run multiple instances of DataStage on UNIX and Winodws using VMWare's products without any problems at all.

DS4DRIVER · Post by **DS4DRIVER** » Wed Jan 04, 2006 3:54 pm

Hi,
Yes, the Network Admin has created a new Logical Host with its own VIP Address. I am going to use -itag option for the installation. I checked if any other services is using hexITAG "apd" (ipcs -m | grep apd), and i did not find one. Can i pass anything as hexITAG value (as long as it is not used) as a parameter to the INSTALL.SH program.

Thanks,

ArndW · Post by **ArndW** » Wed Jan 04, 2006 4:59 pm

Woah - if your "logical host" is the same as another virtual machine then you don't need to use a different memory address! You really only need to do this if two intances of DataStage need to co-exist on the same UNIX node; and from what I gather this is not the case.

tcj · Post by **tcj** » Wed Jan 04, 2006 7:34 pm

I am interested in what scenario you would need two instances of the same Datastage Server version on the same box. Just out of curiosity

ray.wurlod · Post by **ray.wurlod** » Wed Jan 04, 2006 7:36 pm

One physical machine but two separate machines as far as the rest of the world is concerned. Don't really understand the need for two copies of the same version either - using multiple projects would seem to do it for me. Maybe they want one with NLS and one without?

ArndW · Post by **ArndW** » Thu Jan 05, 2006 2:16 am

Ray,

the site I am at has not only numerous machines but also several instances of DS on many of them. Although originally intended for temporary use during migration, they work out quite well. They are almost a 24x7 operation and "bouncing" a DS instance can take days to arrange, with more instances and therefore less users and jobs on them it becomes easier to manage. In addition, this installation has hit some DataStage imposed limits on the number of concurrently started/running DS jobs, by putting two instances on one machine this restriction has been circumvented. The downside is added overhead (especially in shared memory), having to attach to the correct engine directory for the instance you want to look at from UNIX, and having to remember connection port numbers for each instance.

tcj · Post by **tcj** » Thu Jan 05, 2006 6:10 pm

ArndW wrote:Ray,

the site I am at has not only numerous machines but also several instances of DS on many of them. Although originally intended for temporary use during migration, they work out quite well. They are almost a 24x7 operation and "bouncing" a DS instance can take days to arrange, with more instances and therefore less users and jobs on them it becomes easier to manage. In addition, this installation has hit some DataStage imposed limits on the number of concurrently started/running DS jobs, by putting two instances on one machine this restriction has been circumvented. The downside is added overhead (especially in shared memory), having to attach to the correct engine directory for the instance you want to look at from UNIX, and having to remember connection port numbers for each instance.

Interesting.

Wouldn't having two instances of the same DS version on the same machine be a violation of the license? (no I do not work for IBM

)

I thought that the hardware would of been the limit of the number of jobs concurrently started/running. Interesting that it is DS that has the imposed limits. Must be some big machines that DS is running on?

Tim