During some recent work we discovered a very interesting bug with Cisco 6500 and specifically their WS-X6708-10GE and WS-X6716-10GE cards. When installing the cards into 6509 or 6513 chassis it can cause an existing module to reload so if you happen to have chosen slot 9-13 you have a issue. The 8th slot above the one you install the card into will reload. So if you place in slot 9, slot 1 may reload. The interesting example I can think of is if you happen to be using a 6513 and install in slot 13 which slot is 8 above…..yes slot 5 which will be your supervisor card!

The bug details can be found below, however I like the workaround of powering the switch down to replace a hot swappable card.

CSCsz13049 W2.b: OIR 6708 to create bus stall in slot 12 cause reset on slot 4
Externally found severe (Sev2) bug: R-Resolved

The release notes are:

When a WS-X6708-10GE module or a WS-X6716-10GE module is inserted into a 6509 or 6513 chassis it may cause the module in slot N-8 to reload.
For eg. Insert into slot 9 may reset module in slot 1
Insert into slot 10 may reset module in slot 2
so on ..
Insert into slot 13 may reset module in slot 5

There is no problem when removing the module from slots 9-13


  1. The 6708/6716 module should be inserted in slots 9 to 13.
  2. Module insertion is done slowly.

Workaround :

  1. Use slots other than 9 to 13 when inserting a 6708/6716 module.
  2. Insert the module when the switch is powered down.

As a workaround provided to previous customers that saw the exact problem, please refer to the following steps:

When seating the module, initially slide the module into the place, but do not let the locking arms close more than 45 degress. At this point the module is ready to be seated, but is not contacting the backplane.

When ready to fully seat the module, close the locking arms from the > 45 degree angle to fully closed. This must be done in less than 5 seconds. This should be easy to perform in less than 5 secs as the remaining angle for the arms are closed at steady rate.