Layer 2 Networks and EqualLogic SANs

Question

One of the most important steps in planning for an iSCSI SAN is properly determining the size of the SAN solution required then sizing the network infrastructure appropriately to allow for current AND future growth. I am currently working a whitepaper that will be released soon that looks at Layer 2 switches such as the PowerConnect 54xx Series and helps in determining if a layer 2 network solution (and the PC54xx in particular) can handle a SAN of the size you are looking at.

How many ports does it take to actually implement an EqualLogic SAN?

Working with the Dell EqualLogic engineering team in Nashua and with the PowerConnect team here in Round Rock, I came up with a quick formula to determine the number of ports you need:

(([#Arrays]x 6) + ([# hosts]x 2) + ([#Active PSArray Ports] x 2))
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2

For the details you will have to wait for the full paper, but thought you might find this of use.

arthurvino1 · Answer

'One of the most important steps in planning for an iSCSI SAN is properly determining the size of the SAN solution required then sizing the network infrastructure appropriately to allow for current AND future growth. I am currently working a whitepaper that will be released soon that looks at Layer 2 switches such as the PowerConnect 54xx Series and helps in determining if a layer 2 network solution (and the PC54xx in particular) can handle a SAN of the size you are looking at. How many ports does it take to actually implement an EqualLogic SAN? Working with the Dell EqualLogic engineering team in Nashua and with the PowerConnect team here in Round Rock, I came up with a quick formula to determine the number of ports you need: (([#Arrays]x 6) + ([# hosts]x 2) + ([#Active PSArray Ports] x 2)) --------------------------------------------------------------------------------- 2 For the details you will have to wait for the full paper, but thought you might find this of use.' Cool formula. My Dell rep says only Cisco switches are certified with Equalogic.. By looking @ your message I would assume that his statement is incorrect?

DELL-Tony A · Answer

Thanks for the comment!

The PC5400 series is an approved switch for EqualLogic. The PC6200 series is not currently approved.

Note that Layer 2 switches are somewhat limited in their ability to scale beyond 3 arrays, so if you plan on needing more storage now or in the future, you will be better off going with a stacking switch like the Cisco 3750.

arthurvino1 · Answer

'Thanks for the comment! The PC5400 series is an approved switch for EqualLogic. The PC6200 series is not currently approved. Note that Layer 2 switches are somewhat limited in their ability to scale beyond 3 arrays, so if you plan on needing more storage now or in the future, you will be better off going with a stacking switch like the Cisco 3750. ' Thanks Tony. Cisco 3130x is Certified for iSCSI/Equalogic? 3750 does seem like a great choice as well.

DELL-Tony A · Answer

Arthur,

Sounds like you are using an M1000e blade chassis solution, so the 3130 X or G would be the appropriate switch models to use with EqualLogic. The X model gives you the ability to use 10G-Ethernet allowing for some future-proofing as 10G comes to the market sometime next year.

Tony

wwolfram · Answer

' 3750 does seem like a great choice as well.' The original formula that Tony posted is based on 2 switches... thus the division by 2. The idea behind the ([#Active PSArray Ports] x 2)) part of the equation is to avoid bottlenecks in the network... That is why we implement equal interswitch links to # of active EQL ports.... The Cisco 3750's are stackable... have high speed interconnect between eachother that make it a very nice solution for EQL switching (we avoid ISL's that take up ports).... the number of ports used if 3750's are implemented is simply: (([#Arrays]x 6) + ([# hosts]x 2) .

FluidFS

Layer 2 Networks and EqualLogic SANs

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