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How I/O request is processed in EVA and MSA

Raja N
Occasional Contributor

How I/O request is processed in EVA and MSA

Hi,
Can any one please explain me how I/O request is processed by EVA and MSA(1500/1000) storage controllers.I need step by step process.


Thanks
Raja
4 REPLIES
IBaltay
Honored Contributor
Raja N
Occasional Contributor

Re: How I/O request is processed in EVA and MSA

Thanks Baltay.

In active/Passive scenario how I/O requests are sent to exactly active controller though both controllers are connected to the fabric.

Raja N
Occasional Contributor

Re: How I/O request is processed in EVA and MSA

In other words how active controllers are identified and sent I/O requests in active/passive scenario though both the controllers are connected to fabric/host.
IBaltay
Honored Contributor

Re: How I/O request is processed in EVA and MSA

active/passive
Reads/Writes always via one controller either A or B

active/active
writes always via both controllers to both caches (mirror ports)
good reads via the so called managing controller - negotiated by MPIO ALB
bad reads viac the so called proxy controller - via the mirror port and the managing controller
the pain is one part of the reality