ODS400 & OMS400
Home > IT Answers > AS/400 > ODS400 & OMS400
Mandrax100
5 pts.
0
Q:
ODS400 & OMS400
i5, HA, i5 570, ODS400, OMS400
We have two 570 systems, which have a dedicated 1 Gb Ethernet link between the machines for replicating "Realtime" data as part of their HA solution. The replication software has a lag threshold setting currently set to 20 mins and warns when this is reached. Initially there was 1 queue setup to send the data between the systems and this has been increased to two and more recently to three to keep it under 20 mins to try and resolve this but with limited success.
During the last two weeks however we are starting to see the threshold breached each day with one queue becoming an hour and a half behind in lag time. I'm trying to ascertain if the link is becoming 'saturated' , which I will need to raise as a risk to the clients business if this is the case.
Currently there are three send jobs from source to target.

Anyone ever experienced the 'lag' effect and how to circumvent it?
ASKED: Oct 28 2008  3:48 PM GMT
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
RELATED QUESTIONS
0
CAZAWI
85 pts.
0
A:
 RATE THIS ANSWER
0
Click to Vote:
  •   0
  •  0
  • AddThis Social Bookmark Button
Hi,
We had the same issue in the beining of our HA project, we have 2Mb line transfert between tow systems, to circumvent the lag, especialy when the activity increase we purchase a hardware solution which consist in a line compressor, we install one compressor in a production site and the other on the backup site.Now we are in 1s lag


Regards



KAZAWI
Last Answered: Oct 28 2008  6:06 PM GMT by CAZAWI   85 pts.
  •   
0
0
RSS - Discussions Help
Discuss This Answer:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _



_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Slack400   1165 pts.  |   Oct 29 2008  7:36PM GMT

You really should contact your HA Vendor.

I had a similar issue but it was traced to a lack of knowledge or understanding of a network admin to properly configure our switching equipment between sites.

You should be able to gather some metrics from your activity logs within the HA product or run SATLITE.
If you find this lag hitting the same time each day then you probably had a change in your environment that’s increased your data changes recently.

If you find you’re replicating tons of work files or query files that aren’t necessary for HA then you may want to flag those files to not replicate changes.

In my environment over 40% of our changed data is by queries and work files.

Slapping on an appliance maybe a good idea but that’s extra costs and complexity to your HA environment and it really should be the last choice.

 

Mcl   2500 pts.  |   Oct 30 2008  7:17PM GMT

We’re running OMS400 and ODS400 - 570 to a 520 - 1 Gb non-dedicated line. Three “links” - we do see some delays - but not often. Our target system is also in another city, so sometimes our delays are network induced.

As Slack400 suggests, try tuning your replication to eliminate objects that you don’t need.

You can also look at your source and target systems for problems that might cause performance hits. Things like DASD usage, cache battery status..

Regards
Mike

 
0