How many ports can be spanned safely

a-craick · ‎07-24-2003

We're setting up an IDS on the lan and we currently use 2 4006 switches with a trunking fibre running between the two.

We need some way to span all traffic on both switches to one switch port. It doesn't matter which switch it is as long as all traffic is replicated to the one 100BaseTX port.

Is there any way of doing this ?

Also are there any limits to the amount of active ports that should be spanned to a single port before performance on the switch will degrade ?

t.baranski · ‎07-25-2003

You can use RSPAN to have traffic from multiple switches SPAN'd to a single port. The performance impact of SPAN ports on various switches is addressed here: http://www.cisco.com/warp/public/473/41.html

a-craick · ‎07-29-2003

thankyou. Very helpfull infromation.