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SRDF bandwidth utilization

Planning to implement SRDF/A and our network group is giving 2x400mb/s redundant links.They were saying that the bandwidth utilization is up to storage devices means we can throttle 800 out of this.I have this basic question.If we connect these links to two adapter each 400mb,how does Symm distributed the load?Is it going to do load balancing? or is it going to use only one link?

Any thoughts?
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Re: SRDF bandwidth utilization

SRDF will always use any available link to push data to remote side.
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Re: SRDF bandwidth utilization

Thanks Stefan!What kind of mechanism does it use?Do i need to configure anything on the symm.
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Re: SRDF bandwidth utilization

You are welcome .. :-)

I have no further details .. I've simply experienced this behaviour in the last few hour .. my customer removed 4 DWDM link, breaking half of our SRDF links .. SRDF handled the issue using only available links .. :-) ..

Now the customer replaced the DWDM link and all RF adapters are spreading the workload between all paths :D

SRDF have a "PowerPath" inside, spreading the workload and balancing it on every available link .. and resuming paths when links comes back ;-)
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Re: SRDF bandwidth utilization

If you need 800MB/sec, you will need more than two RAs. I would suggest 4.
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Re: SRDF bandwidth utilization

You mean say 4 adapters or divided between 4 ports?
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Re: SRDF bandwidth utilization

4 processors configured as RF. Each RF processor have a single port.
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Re: SRDF bandwidth utilization

It is not MegaBytes..it 80MB or 800Mbits..
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Re: SRDF bandwidth utilization

Ah, sorry. Two RAs are plenty for 80M Bytes/sec. :-)
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Re: SRDF bandwidth utilization

Absolutely ! I've seen 2 RA's of 2Gb each pushing data over 1.2Gbps (1 x 800Mb and 1 x 400Mb using Cisco 9216i's and FCIP) at 400 MegaBytes per second ("some" compression was involved), so if you have a true SAN between the 2 Arrays (not FCIP or something) you theoretically should be able to do 2 x 2Gb on 2Gb ports and 2 x 4Gb on the latests models, so 800MBps. Only 80 is "nothing"....
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