ISl trunk

[Oscar_Maimó]

Hi everybody:
I have a SanSwitch 4/16 and a SanSwitch 4/32.
My question is:
May I interconnect them using 2 ISL cables without ISL trunking license?
What are the difference between 2 ISL cables and a trunk of 2 ISL, from the point of view of performance?
Regards
Oscar

[Oscar_Maimó]

Sorry:
I have a 2/16 and a 4/32

[IBaltay]

Hi,
the trunk aggregates the individual paths into one and preserves in-order deliver of frames, the total throughput is increased compared to a non-trunked group of ISLs. ISL Trunking dynamically performs load balancing, at the frame level, across a set of available links between two adjacent switches to establish a trunking group. Ports that belong to a trunking group are called trunking ports. One port is used to assign traffic for the group, and is referred to as the trunking master.

[Oscar_Maimó]

What happen if I don't use trunking and only use 2 ISL cables?

[IBaltay]

those are 2 separate ISL links without the features described above (for trunk)...
But for trunk you need a special licence whilst for the ISL the full fabric license is sufficient...

[Oscar_Maimó]

Let me do a last question:
What are the benefits of 2 ISL cables without trunking?
Thanks

[IBaltay · Accepted solution]

the ISL link redundancy within one fabric (e.g. across the DWDM or long wave (10kms))...

see also the HP SAN DESIGN REFERENCE GUIDE:
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00403562/c00403562.pdf?jumpid=reg_R1002_USEN

[Uwe Zessin]

Redundancy and simple load sharing.

[Oscar_Maimó]

Thanks boys