Planning to Implement SRDF/A (distance is about 1000 miles between the site).DMX-3 with GigE cards.I was using Symchnage for the data analysis for the tracks changing for every 30 secs.RPO is about 5 mins. -Setting the resync rate for 5 mins with 2 RA adapters is providing me the required bandwidth but is the right value to consider for resynch of 5 mins?I assume resync time is when the link breaks?If that is the case how do calculate the required bandwidth using symchg?
srichev as Julie already explained, this area is the first place where "lite users" can land. However now you should be a regular user and thus be able to browse all forum areas. This thread is better served in the "Symmetrix" area of our forums.
Julie can you please move this thread at correct location ??
srichev I'd use symchange to find how many tracks changes in your box and size bandwidth accordingly. What do you mean with "resync" ?? SRDF/A switches cycles every 30 seconds .. and in case your links drops, resync time depends on outage duration since resyncing after 20 minutes of network disruption is a lot different then syncing after 20 hours of network disruption.
My suggestion is to just look at the raw writes on the volumes you want to sync and use your change tracker data just as a sanity check. My guess is if you have a normal workload mix you will probably see that your rate will be like 20% lower with change tracker than just regular I/O. Obviously your mileage can vary dramatically depending on your workload.
Looking at just writes (and not changed tracks) is the safe call because you get a worst case assumption (which is good for SRDF/A or SRDF/S) and in most normal workloads will not be too overestimated.
Short answer - symchg really is not designed to handle SRDF/A or SRDF/S.