Dell Force10 MXL Manual page 13

Stacking Dell Force10 MXL 10/40G Switches
FTOS(conf)#no stack-unit 0 port p portmode quad
Please save and reload for the changes to take effect.
where p is the port to be converted. Refer to the section
single 40GbE QSFP+ port
Note: MXL stacking support QSFP+ cable lengths at distances of up to 7m. Dell offers cables in lengths
of 1m, 3m, 5m, and 7m that can be used for this purpose.
The Dell Force10 MXL supports stacking across multiple M1000e chassis (known as vertical stacking).
That means it is possible to have six M1000e chassis', each one having an MXL installed with all six MXL
switches being members of the same stack.
Figure 4 shows the connectivity between the stack members in M1000e chassis slots A2, B2, and C2
using a single 40Gb stacking port. Figure 6 5 shows the connectivity between stack members across
multiple M1000e chassis using two stacking ports between members. All slots (A1, A2, B1, B2, C1, C2)
in the M1000e are supported, and any of these slots can be used to stack along with any other slot or
set of slots. There are no limitations as to which slots can be used and the number of chassis which can
be used. The only limitation is six MXL devices. The follow lists possible scenarios:

Stacking two to six Dell Force10 MXL switches using any combination of slots A1, A2, B1, B2, C1
and C2 in a single chassis.

Stacking two to six Dell Force10 MXL switches using any combination of slots A1, A2, B1, B2, C1
and C2 in multiple chassis'.
Examples:

Stacking six Dell Force10 MXL switches across six M1000e chassis , using slot A1 in first chassis,
B2 in second, C1 in third, A1 in fourth, B1 in fifth, and B1 in sixth.

Stacking six Dell Force10 MXL switches across two M1000e chassis, using slots B1, B2 and C2 in
chassis 1 and slots B2, C1, and C2 in chassis 2.

Stacking three Dell Force10 MXL switches across two M1000 chassis, using two slots in the first
chassis and only one slot in the second.

Any other way of stacking up to six MXL switches in up to six chassis.
Note: It is also possible to have multiple stacks in a single chassis (horizontal stacking) or across
multiple chassis' (vertical stacking).
for more details on how to use this command.
Combining split 10GbE SFP+ ports into a
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