This is important!! Now, you would think that when you look at the weather channel and the person tells you there is a wind coming from the North the direction is from North to South. This could be interpreted somewhat different when he or she tells you there is a “northerly” wind. Does the later mean it’s coming from the North or is it going to the North. The same is now true for Brocade 65xx series switches. The 6505/6510 have a different interpretation of how the wind blows than the 6520 series. Is it moving forward or reverse, is it coming from the front or back and on which side is the intake and/or exhaust and which spare-part do you need to order in case one fails, xx-F or xx-R. If you order the wrong one the switch will tell your this after which it will shut down. Whoops. The documentation also shows some confusion around the PS acronym. Is it now related to the airflow, in which case it stands for Port-Side, or does it mean Power Supply when a FRU is meant?

It looks like a set of different engineers have been using the above terminology and got confused themselves therefor making assumptions and this didn’t really fan out well. I’m sure they will correct it in the near future with some newer code and adjust the documentation.

So here’s how it is.

On the 6505 and the 6510:

When the intake is from the rear and the exhaust is on the port-side you should see the following:

• Orange “I” sticker on the power supply/fan FRU
• Power supply spare part number should end with -R
• The powersupply/fan FRU is XBR-5100-0001
• When looking in the chassisshow output you should see “Forward”
  • FAN Unit: X
  • Fan Direction: Forward
• No spare-part number in any of the logs
• * the 5100 in the PS/fan FRU is the same as for the 5100

When the intake is from the front and the exhaust is at the back:

• Green “E” sticker on the powersupply/fan FRU’s
• Chassis spare partnumer ends with a -F
• Power supply spare part number end with an -F
• FRU partnumber is XBR-6510-0001
• The chassisshow output mentions “Reverse”

On the 6520 the above is the other way around.

Intake from the front and exhaust at the back.

• Green “E” sticker on the powersupply/fab FRU’s
• -F is in the chassis spare-part number
• Chassisshow shows ‘Forward”.
• The powersupply spare FRU is XBR-1100WPSAC-F
• The fan FRU partnumer is XBR-FAN-80-F

Intake from the rear and exhaust at the front.

• Orange “I” sticker on powersupply and fan FRU’s
• Sparepart number end in -R
• The chassisshow output shows ‘Reverse”
• Powersupplu spare part is XBR-1100WPSAC-R
• The fan spare part number is XBR-FAN-80-R

As mentioned, this might change in the future when brocade is modifying FOS to show the correct airflow in the logs and CLI chassisshow output. I certainly hope there won’t be more platforms where this happens.

It doesn’t happen often that a powersupply or fan fails. I’ve been working with Brocade switches for more than 15 years and I’ve seen switches with powersupplies and fans working for over 5 years. (I replaced it with newer gear so I couldn’t determine for how long it would last in the end.)  Not really a problem but this is just to make you aware of the discrepancy.

Cheers,

Erwin