NetApp port descriptions and what to do with e0M, SP and ACP

The current NetApp lineup has a variety of ports on the back which can be confusing to even the most experienced admin.

A FAS3240 (single-chassis HA) for example has two SAS, two GBIC slots, two GBICs with FCP modules, five RJ45 and a USB – and that’s without using the two PCI expansion slots or the chassis I/O expansion.

Here I’ll break down the ports you see on the back of a FAS3240 and describe the three “new” management methods e0M, SP and ACP.

The documentation that ships with the controller has a good legend to help decipher the icons printed by each connection:

And a picture of the chassis, just in case you are not standing next to it.

I’ll go left-to-right

7: SAS cables for your external SAS shelves. 0a, 0b. If you ordered your filer with SAS shelves it should have shipped with cables. Note that you can multi-path shelves with SAS just like FCP.

8: HA cables. c0a, c0b. If you buy a multi-chassis filer (ie you want a FAS3240 with the expansion module you’ll get two physical chassis) or want to do metro-cluster. Note also – these are 10G Ethernet ports but they have OS-set IP addresses and cannot be used for anything but HA.

6: FCP. 0c, 0d. Used for connecting to Fibre Channel switches, shelves or tape drives (for NDMP backups)

3: e0a and e0b. Two 1GB Ethernet adapters for network access and traditional management. iSCSI, CIFS, NFS, http will all use these ports.

4: Unlocked management. e0M / SP combo port. This is the successor to BMC/RLM out-of-band management port. It adds a twist in that port e0M on the filer shares this port (there is an internal hub). You can configure just the SP port (sp setup) and use it for out-of-band management, you can also configure e0M from the filer which will use this port for in-band management – Filerview, System Manager etc. Note that you are required to have e0M on a separate IP network than your other ethernet ports, and it is required to be on the same network as the Service Processor. It is possible data (iSCSI, NFS, CIFS) traffic will go out this port as a last resort – but it won’t have it’s own default gateway. This needs to be on a dedicated management-only network. Do not configure e0M unless you intend to use it – the filer will default management traffic to it if it is configured.

5: Locked management. e0P. Used for Alternate Control Path (ACP) Out-Of-Band (OOB) management of SAS shelves More and More

1/2: Serial port and RJ45-to-DB9 adapter. Used to manage the filer via console. Note you’ll need one of these if you have a modern system to connect the old-school serial cable up to your modern USB port. Don’t forget putty also.

Not labeled: USB. Currently described as “unused”

Always configure SP. Don’t configure e0M unless SP is connected to a dedicated management network. Always connect the ACP cables (hey, you paid for it!).
Always multipath SAS and FCP when you have the ports available.
Always take the lifeboat with the motor.

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21 Responses to NetApp port descriptions and what to do with e0M, SP and ACP

  1. Great write-up, very handy

  2. dmcneil says:

    Helpful reference, thank you

  3. Fadal Sayed says:

    Well written… thanks a lot buddy

  4. Atila says:

    Precise and to the point. Well done!

  5. Boris Kürten says:


  6. Hajee says:

    This is very informative 🙂

  7. bentlema says:

    Is the SP hardwired to the management (unlocked wrench port)? We have a 2240-4, and are wondering if the SP must be accessed via the management port, or can it be configured to be accessed via one of the other ports (e0a, e0b, e0c, e0d)? It sounds like, as you’ve said the e0M and SP are hardwired to an internal switch (you said hub) behind the management port, that it must be accessed via the management port, but just trying to confirm my understanding is correct.

    One issue we’re seeing is that the management port is 100Mbps-fdx only (not 1Gig) and our Cisco Nexus switch apparently doesn’t support that speed (I’m told by our Network Admin), so we’re trying to find a way to get our SP on the network.

  8. Moh.Elfatih says:

    Can I change c0a & C0b for 10 G port whith out HA

  9. Shubhang Varma says:

    Thanks! Very helpful.

  10. Seb says:

    Helpful, thank you.

  11. Mark Peluso says:

    Hello: I have a dual-port 10G PCI card in our FAS3240. The ports show up as e1a and e1b. I am trying to configure iSCSI protocol on these ports but iSCSI only seems to be supported on the 1G e0a/e0b interfaces. is there a way to move the iSCSI to 10G?

    • Sorry it’s been a long time since I’ve supported NetApp appliances. If you purchased the 10G PCI from NetApp and have it licensed for iSCSI it should certainly work but you’ll want to verify with NetApp that everything is in order.

  12. Bilal Ahmed says:

    This came in handy for me when studying for my NCSA

  13. Dino says:

    First of all many thanks for this article. It’s pretty clear and useful article for a newbie like me to NetApp arrays.

    It would be great if you could elaborate a little on what is SP and EOM

  14. Krishna says:

    To the point and well explained. Excellent Job.

  15. romain says:

    I’ve some questions about port roles and cabling to 10G switches.
    I’ve 2xFAS3270 HA and 10Gb cards.
    c0a & c0b connected to each others.
    additionnal card 10G (e1a & e1b)

    I plan to to add another 10G cart (e2a & e2b).

    Then I will setup :
    e1a & e1b as cluster role
    e2a & e2b as data role.

    Do you think this is a good setup ?

    Today I’ve only one 10G card, and can’t define how to optimize 10G network. Should I use 10G ports for data role or cluster role ? Or one for each role ?

    Hope you can help.

  16. Bhaskar says:

    Thanks buddy it helped a lot

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