I am not sure about the 2948, however with the 2950T it is spanning-tree portfast applied from the interface.
2840-1st-sw1(config-if)#int fa0/1 2840-1st-sw1(config-if)#spanning-tree portfast %Warning: portfast enabled on FastEthernet0/1. Usually portfast should be enabled on ports connected to a single host. When portfast is enabled, connecting hubs, concentrators, switches, bridges, etc. to this interface may cause temporary spanning tree loops. Use with CAUTION. Don Pezet wrote: > > Priscilla and Cisco_Maniac, > > Well, I have been tinkering around with it a bit more (which is > pretty much how I got here) and here are my findings. First, I > went > ahead and did a 'debug span events' on the 2948G-L3 and noticed > no > convergence issues... actually no events at all. A quick 'show > span' > returned the following: > > -------------------------------------------- > Bridge group 1 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0001.c779.f807 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 1, topology change 0, notification 0 > bridge aging time 300 > > Port 4 (FastEthernet1) of Bridge group 1 is forwarding > Port path cost 19, Port priority 128 > Designated root has priority 32768, address 0001.c779.f807 > Designated bridge has priority 32768, address 0001.c779.f807 > Designated port is 4, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40808, received 0 > > ... Removed additional ports (2 - 46) > > Port 50 (FastEthernet47) of Bridge group 1 is forwarding > Port path cost 19, Port priority 128 > Designated root has priority 32768, address 0001.c779.f807 > Designated bridge has priority 32768, address 0001.c779.f807 > Designated port is 50, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40865, received 0 > > Port 54 (FastEthernet48.1 ISL) of Bridge group 1 is forwarding > Port path cost 19, Port priority 128 > Designated root has priority 32768, address 0001.c779.f807 > Designated bridge has priority 32768, address 0001.c779.f807 > Designated port is 54, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40867, received 0 > > Port 56 (GigabitEthernet49.1 ISL) of Bridge group 1 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0001.c779.f807 > Designated bridge has priority 32768, address 0001.c779.f807 > Designated port is 56, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40874, received 5 > > Bridge group 2 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0001.c779.f836 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 0, topology change 0, notification 0 > bridge aging time 300 > > Port 55 (FastEthernet48.2 ISL) of Bridge group 2 is forwarding > Port path cost 19, Port priority 128 > Designated root has priority 32768, address 0001.c779.f836 > Designated bridge has priority 32768, address 0001.c779.f836 > Designated port is 55, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40867, received 0 > > Port 57 (GigabitEthernet49.2 ISL) of Bridge group 2 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0001.c779.f836 > Designated bridge has priority 32768, address 0001.c779.f836 > Designated port is 57, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40876, received 6 > > Bridge group 10 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0001.c779.f907 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 1, topology change 0, notification 0 > bridge aging time 300 > > Port 58 (GigabitEthernet49.10 ISL) of Bridge group 10 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0001.c779.f907 > Designated bridge has priority 32768, address 0001.c779.f907 > Designated port is 58, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40874, received 4 > > Bridge group 20 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2af8 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 0, topology change 0, notification 0 > bridge aging time 300 > > Port 59 (GigabitEthernet49.20 ISL) of Bridge group 20 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2af8 > Designated bridge has priority 32768, address 0000.0c97.2af8 > Designated port is 59, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40874, received 3 > > Bridge group 30 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b00 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 0, topology change 0, notification 0 > bridge aging time 300 > > Port 60 (GigabitEthernet49.30 ISL) of Bridge group 30 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b00 > Designated bridge has priority 32768, address 0000.0c97.2b00 > Designated port is 60, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40874, received 4 > > Bridge group 40 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b04 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 1, topology change 0, notification 0 > bridge aging time 300 > > Port 61 (GigabitEthernet49.40 ISL) of Bridge group 40 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b04 > Designated bridge has priority 32768, address 0000.0c97.2b04 > Designated port is 61, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40875, received 4 > > Bridge group 50 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b0c > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 1, topology change 0, notification 0 > bridge aging time 300 > > Port 62 (GigabitEthernet49.50 ISL) of Bridge group 50 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b0c > Designated bridge has priority 32768, address 0000.0c97.2b0c > Designated port is 62, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40875, received 4 > > Bridge group 60 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b10 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 1, topology change 0, notification 0 > bridge aging time 300 > > Port 63 (GigabitEthernet49.60 ISL) of Bridge group 60 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b10 > Designated bridge has priority 32768, address 0000.0c97.2b10 > Designated port is 63, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40875, received 3 > > Bridge group 70 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b18 > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 0, topology change 0, notification 0 > bridge aging time 300 > > Port 64 (GigabitEthernet49.70 ISL) of Bridge group 70 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b18 > Designated bridge has priority 32768, address 0000.0c97.2b18 > Designated port is 64, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40875, received 4 > > Bridge group 80 is executing the IEEE compatible Spanning Tree > protocol > Bridge Identifier has priority 32768, address 0000.0c97.2b1c > Configured hello time 2, max age 20, forward delay 15 > We are the root of the spanning tree > Topology change flag not set, detected flag not set > Times: hold 1, topology change 35, notification 2 > hello 2, max age 20, forward delay 15 > Timers: hello 0, topology change 0, notification 0 > bridge aging time 300 > > Port 65 (GigabitEthernet49.80 ISL) of Bridge group 80 is > forwarding > Port path cost 4, Port priority 128 > Designated root has priority 32768, address 0000.0c97.2b1c > Designated bridge has priority 32768, address 0000.0c97.2b1c > Designated port is 65, path cost 0 > Timers: message age 0, forward delay 0, hold 0 > BPDU: sent 40876, received 4 > ---------------------------------------------------------- > The only interface on the 2948G-L3 that should be receiving any > STP updates would be G49 and its subinterfaces, as that is the > ISL trunk > to the 3548XL stack. I see a few scattered updates probably > from routing > STP maintenance or from power outages over the weekend (the > UPSs tapped > out at different intervals, always nice) but nothing unusual. > Certainly > not enough to mirror the connection loss interval of the > workstations. > > Anyhow, so I started thinking along the lines as Cisco_Maniac > about enabling portfast and just seeing what happens, but the > 2948G-L3 > uses a Router's IOS and so it doesn't support portfast as far > as I can > tell. Anyone familiar, off hand, with how to do portfast on the > 2948G-L3? CCO was unhelpful (or more likely my searching > abilities). > > On the performance issue, I'll be running bandwidth tests > between stations on separate VLANs today to see exactlly what > throughput > I am able to get while being routed by the 2948G-L3 today. If > it is > actually performing worse than the 3620 when it was bottle > necking I may > just move the network back to the old configurations. We'll see > what > happens and I'll post the results. > > As always, thanks for your help, > > Don Pezet > Enterprise Technology Solutions > [EMAIL PROTECTED] > (352) 248-1010 > > On 12 Aug 2002 08:39:20 -0000, in groupstudy.cisco you wrote: > > >If that is the case Priscilla, then one might as well enable > Port-Fast > >on a those ports and observe for a few days. If the switch > activity > >stabilizes then it is surely a STP re-convergence problem. Am > I on > >track? Chaoo, Cisco_Maniac > >""Priscilla Oppenheimer"" wrote in message > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > >> You say that the stations connected to the 2948G-L3 stop > transmitting > > >> for > >15 > >> seconds. Could the Spanning Tree be reconverging for some > reason? > >> Since you're doing IRB with both bridging and routing, > presumably STP > > >> is running and 15 seconds sticks out as the Forward Delay > timer used > >> by STP. It's > >also > >> the timer for aging the bridging table when BPDUs arrive > with the > >> Topology Change Flag set. > >> > >> I can't see why the change you made would cause a problem, > but maybe > >> it > >did > >> for some reason or maybe it caused you to hit a bug. You may > want to > >> try "debug span events" or the equivalent if that doesn't > work on a > >> 2948G-L3. > >If > >> debug is too risky, "show spantree" might give you some > hints as to > >> when > >the > >> last topology change occured. > >> > >> It's just a guess but that 15 seconds sure sticks out as a > possible > >> clue that something is up with Spanning Tree. > >> > >> Hopefully somebody else will have ideas too! > >> > >> Priscilla > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=51248&t=51240 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
