tag:blogger.com,1999:blog-3266263034124005485.post8195004196016140722..comments2024-03-24T23:19:30.504+00:00Comments on Fragmentation Needed: VTP pruning - not all it's cracked up to bechris margethttp://www.blogger.com/profile/09716555871346949419noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-3266263034124005485.post-30533681781021934692011-02-04T07:01:20.279+00:002011-02-04T07:01:20.279+00:00It is also worth noting that VTP pruning does not ...It is also worth noting that VTP pruning does not help reduce your logical port count for STP limitations. For example, a 6500 running PVST+ can handle 1,800 logical interfaces per slot. With 500 VLANs forwarding on each trunk port, that means you max out at only 3-4 ports used on each slot.<br /><br />VTP pruning does nothing to help this. Every VLAN on the switch is considered by STP to be forwarding out every trunk port. Only "switchport trunk allowed vlan" will actually remove the STP logical interface for the unwanted VLANs from that port.<br /><br />Disclaimer: I have exceeded the recommended 1,800 limit by more than 200% without serious issue. However, go too far and you'll find that one day (for example when a switch reboots) things will never reconverge.Unknownhttps://www.blogger.com/profile/04684230920854245133noreply@blogger.com