We currently have two 6509's that are supposed to be linked together to provide redunendcy in our network. Problem is everytime we bring up the secondary core we begin experiancing problems on the network. Printers letting their print jobs dissappear into no where, high util. on novell server, something different everytime.<br><br>I was wondering if anyone out there had experianced any similar problems?<br><br>Brian Morritt
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6509's for Core switches
- Thread starter bmorritt
- Start date
Sounds like you may be experiencing spanning tree (STP) loops / broadcast storm.
Are you splitting up user groups / IP subnets into separate vlans (not using default/management vlan 1 for user traffic)?
Running VTP (enabled) w/consistent VTP domain name & password on all switches? Set (all) switches as VTP servers?
Are your 6509's being used as distribution switches (vs. "core" switches in the Cisco vernacular),i.e., are they
- terminating dual uplinks from access switches (in your closets)?
- uplinks trunking multiple vlans (config'd as ISL or dot1q trunks)?
- providing ports for central servers?
- routing/L3 switching (MLS) by using MSFC's in each?
If so, check or try load balancing vlans by
- assiging one 6509 as the root bridge for half the vlans (or whatever split divides the traffic load best) on that switch, the other 6509 for the rest. Ex: switch A, vlans 2,4,6; switch B, vlans 3,5,7 ("set spantree root"
- setting vlan port priority on access switch trunks to appropriate root bridges (trunk with lower priority value - per vlan - forwards that vlan traffic on that trunk; other trunk blocks unless primary trunk drops) ("set portvlanpri" Ex: on trunk 1/1, vlan 2 has priority value=1, vlan 3 has pri=32; on trunk 1/2, vlan 2 has pri=32, vlan 3 has pri=1. vlan 2 fwd'd on 1/1, blocked on 1/2 & vice versa for vlan 3.
- do the same for (all) vlans on trunks between your 2 6509 (active) Sup's. Config trunks on both switches the same. If running duals Sup's in each switch, cable 1/1 to 1/1, 1/2 to 1/2.
Hope this helps
Are you splitting up user groups / IP subnets into separate vlans (not using default/management vlan 1 for user traffic)?
Running VTP (enabled) w/consistent VTP domain name & password on all switches? Set (all) switches as VTP servers?
Are your 6509's being used as distribution switches (vs. "core" switches in the Cisco vernacular),i.e., are they
- terminating dual uplinks from access switches (in your closets)?
- uplinks trunking multiple vlans (config'd as ISL or dot1q trunks)?
- providing ports for central servers?
- routing/L3 switching (MLS) by using MSFC's in each?
If so, check or try load balancing vlans by
- assiging one 6509 as the root bridge for half the vlans (or whatever split divides the traffic load best) on that switch, the other 6509 for the rest. Ex: switch A, vlans 2,4,6; switch B, vlans 3,5,7 ("set spantree root"
- setting vlan port priority on access switch trunks to appropriate root bridges (trunk with lower priority value - per vlan - forwards that vlan traffic on that trunk; other trunk blocks unless primary trunk drops) ("set portvlanpri"
Ex: on trunk 1/1, vlan 2 has priority value=1, vlan 3 has pri=32; on trunk 1/2, vlan 2 has pri=32, vlan 3 has pri=1. vlan 2 fwd'd on 1/1, blocked on 1/2 & vice versa for vlan 3.- do the same for (all) vlans on trunks between your 2 6509 (active) Sup's. Config trunks on both switches the same. If running duals Sup's in each switch, cable 1/1 to 1/1, 1/2 to 1/2.
Hope this helps
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