Difference between normal LC-LC FC cable vs Shelf to Shelf cable

[DHAKSHINAMOORTHY_B]

Hi All,

We have FAS3250 (ONTAP 8.1.3 P3). 10 FC shelves and 3 SATA shelevs attached. System configuration is "Multipath-HA"

I had look physical connectivity and i see LC-LC FC cable connnected from controller to Shelf In. But, for shelf to shelf connectivity black colour small cables used. (see attached)

What is the difference between normal LC-LC FC cable vs Shelf to Shelf cable?

Please clarify me on this.

[aborzenkov]

Shelf to shelf are copper with integrated SFP.

[DHAKSHINAMOORTHY_B]

Hi,

Is there any speed, link data rate difference between those two?

[scottgelb]

There are different versions of this shelf to shelf cable...some rated for 2GB (ESH2) and others rated for 4GB (ESH2 and ESH4).  Make sure from the manufacturer part number that you have the correct one if using 4GB on the stack.  The 2GB ones work but throw errors and the only way I remember to identify them was a physical inspection (0018 in the manufacturer part number but it has been a while since we installed DS14s).

[aborzenkov]

IIRC long (3 m) cables are not qualified for 4G; short (0,5 m) are. Additionally, NetApp did bit support copper cables for controller to shelf connection (with exception of FAS270).

[scottgelb]

With the 0.5 the cables with 0018 were 2gb only. 0036 and higher were 4gb from what I remember.

Sent from my iPhone 5

[aborzenkov]

Out of curiosity - do you have any reference? I dug out CSB-0907-03, but it says exactly the same - no 3 m for 4G; it does not say anything about different 0.5m cables.

[scottgelb]

I will see what I can dig up. I remember a customer had loop instability and we found it was the older 0.5 cables with the 018 oem part number that were rated for 2GB only.

Sent from my iPhone 5

[scottgelb]

I couldn't find any KB on this but between my archive of old cables and some ebay searches I found the 3 different SFP 0.5M cables. The NetApp 112-00045 or Molex 739290018 was what I remember caused a problem on 4GB loops...rated for 2GB from what I remember (even though they initially worked but caused instability at 4GB).  Wish there was a KB on it or my memory was better, but the good news is none of us are installing these anymore unless a really legacy system where we can get the newer x6530 cables low cost anyway.

So (based on my fading memory ) be cautious of 4GB ESH4 loops if you have any shelf-to-shelf part numbers of 112-00045 / 739290018...but support can probably find a reference if a customer is using these and needs to confirm 100)%.

NetApp Manufacturing part number 112-00045 (Molex part number 739290018)... 2GB only cable (from what I remember)

NetApp Manufacturing part number 112-00084 (Molex part numbers 739290024 and 739290036)... both Molex part numbers were the same netapp part number...for X6530 cables... 2/4GB cable.