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Disabling STP on Cisco 2948G-L3
- Thread starter Trunks
- Start date
Portfast is enabled per interface. in global config mode, go to configure each interface, eg. int fast 0/1
the command to enable portfast is
spanning-tree portfast
Don't use portfast on any port that is connected to another switch or router.
Cheers
Phil.
the command to enable portfast is
spanning-tree portfast
Don't use portfast on any port that is connected to another switch or router.
Cheers
Phil.
- Thread starter
- #3
OK, Sorry, you're using CatOS on the 2948 (Doh!)
follow this example and you should be able to configure portfast...
Console> (enable) set spantree portfast 4/1 enable
Warning: Spantree port fast start should only be enabled on ports connected
to a single host. Connecting hubs, concentrators, switches, bridges, etc. to
a fast start port can cause temporary spanning tree loops. Use with caution.
Spantree port 4/1 fast start enabled.
## Then to verify operation...
Console> (enable) show spantree 4/1
Port Vlan Port-State Cost Priority Fast-Start Group-method
--------- ---- ------------- ----- -------- ---------- ------------
4/1 1 blocking 19 20 enabled
4/1 100 forwarding 10 20 enabled
4/1 521 blocking 19 20 enabled
4/1 522 blocking 19 20 enabled
4/1 523 blocking 19 20 enabled
4/1 524 blocking 19 20 enabled
4/1 1003 not-connected 19 20 enabled
4/1 1005 not-connected 19 4 enabled
Console> (enable)
good luck...
Phil.
follow this example and you should be able to configure portfast...
Console> (enable) set spantree portfast 4/1 enable
Warning: Spantree port fast start should only be enabled on ports connected
to a single host. Connecting hubs, concentrators, switches, bridges, etc. to
a fast start port can cause temporary spanning tree loops. Use with caution.
Spantree port 4/1 fast start enabled.
## Then to verify operation...
Console> (enable) show spantree 4/1
Port Vlan Port-State Cost Priority Fast-Start Group-method
--------- ---- ------------- ----- -------- ---------- ------------
4/1 1 blocking 19 20 enabled
4/1 100 forwarding 10 20 enabled
4/1 521 blocking 19 20 enabled
4/1 522 blocking 19 20 enabled
4/1 523 blocking 19 20 enabled
4/1 524 blocking 19 20 enabled
4/1 1003 not-connected 19 20 enabled
4/1 1005 not-connected 19 4 enabled
Console> (enable)
good luck...
Phil.
- Thread starter
- #5
We are running IOS 12.0(7)
When I try to enter the commands you have suggested it comes back with 'unrecognised command', even a "set ?" returns and unrecognised command. Is there anything else I can try on these switches. The symptom is not getting a Novell login prompt from cold boot but its ok when you logoff and logon again. Any Ideas ?
Any help would be much appreciated
When I try to enter the commands you have suggested it comes back with 'unrecognised command', even a "set ?" returns and unrecognised command. Is there anything else I can try on these switches. The symptom is not getting a Novell login prompt from cold boot but its ok when you logoff and logon again. Any Ideas ?
Any help would be much appreciated
Ok IOS...
Telnet to or get a console on the switch. Enter password to get to the
"switch>"
prompt.
then enter enable mode...
"switch>enable"
enter the enable password to get the enable prompt...
"switch#"
enter configuration mode...
"switch#conf term"
then select the interface in global config mode...
"switch(config)#interface fast 0/1"
then tell it to use portfast...
"switch(config-if)#spanning-tree portfast"
repeat for all the ports you want to put into portfast mode then exit from config mode (ctrl-z)... and copy the config to startup...
"switch#copy running-config startup-config"
All the best
Phil.
Telnet to or get a console on the switch. Enter password to get to the
"switch>"
prompt.
then enter enable mode...
"switch>enable"
enter the enable password to get the enable prompt...
"switch#"
enter configuration mode...
"switch#conf term"
then select the interface in global config mode...
"switch(config)#interface fast 0/1"
then tell it to use portfast...
"switch(config-if)#spanning-tree portfast"
repeat for all the ports you want to put into portfast mode then exit from config mode (ctrl-z)... and copy the config to startup...
"switch#copy running-config startup-config"
All the best
Phil.
- Thread starter
- #7
Hi Pete,
I guess that puts you in a bit of a pickle ;-)
what do you get when you type
show spann
in enable mode...
Should look something like:-
Spanning tree 1 is executing the IEEE compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address xxxx.xxxx.xxxx
Configured hello time 2, max age 20, forward delay 15
Current root has priority 32768, address xxxx.xxxx.xxxx
Root port is 45, cost of root path is 14
Topology change flag not set, detected flag not set, changes 874
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0
Then follows a list of the ports included in spanning tree.
Do you get a similar response?
Regards,
Phil.
I guess that puts you in a bit of a pickle ;-)
what do you get when you type
show spann
in enable mode...
Should look something like:-
Spanning tree 1 is executing the IEEE compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address xxxx.xxxx.xxxx
Configured hello time 2, max age 20, forward delay 15
Current root has priority 32768, address xxxx.xxxx.xxxx
Root port is 45, cost of root path is 14
Topology change flag not set, detected flag not set, changes 874
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0
Then follows a list of the ports included in spanning tree.
Do you get a similar response?
Regards,
Phil.
- Thread starter
- #9
Hi Pete, Hmmm.
Ok, check your config register settings.
There is no reason I can think of right now, why you wouldnt have spanning-tree commands under the interface config mode.
If your switch is not connected to any other switch or router you could turn off spanning tree (I really dont recommend this - it's REALLY asking for trouble!!)
in config mode
switch(config)#no spanning-tree
But you might have nailed it earlier, a naff version of IOS (I find it difficult to believe and can't find reference caveats or similar problems with your version). However, probably best to try reinstalling or upgrading the IOS first.
Best o' luck
Phil.
Ok, check your config register settings.
There is no reason I can think of right now, why you wouldnt have spanning-tree commands under the interface config mode.
If your switch is not connected to any other switch or router you could turn off spanning tree (I really dont recommend this - it's REALLY asking for trouble!!)
in config mode
switch(config)#no spanning-tree
But you might have nailed it earlier, a naff version of IOS (I find it difficult to believe and can't find reference caveats or similar problems with your version). However, probably best to try reinstalling or upgrading the IOS first.
Best o' luck
Phil.
- Thread starter
- #11
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The 2948G-L3 is a router when it comes to configuration. First configure a bridge group in global configuration. Then for each interface make sure it is in the bridge group before disabling spanning tree.
interface FastEthernet1
no ip address
no ip directed-broadcast
bridge-group 1
bridge-group 1 spanning-disabled
!
bridge 1 protocol ieee
interface FastEthernet1
no ip address
no ip directed-broadcast
bridge-group 1
bridge-group 1 spanning-disabled
!
bridge 1 protocol ieee
- Thread starter
- #13
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Going back to the original question. Basic assumption that you are running Catalyst IOS.
Spantree is setup on a VLAN and per port/module basis.
Example
Vlan commands at default. If you want to disable spantree
then disable the vlan, ie:
set spantree disable 1 where 1 is the VLAN.
#spantree
#uplinkfast groups
set spantree uplinkfast enable rate 15 all-protocols off
#backbonefast
set spantree backbonefast disable
#vlan 1
set spantree enable 1
set spantree fwddelay 15 1
set spantree hello 2 1
set spantree maxage 20 1
set spantree priority 49152 1
#vlan 16
set spantree enable 16
set spantree fwddelay 15 16
set spantree hello 2 16
set spantree maxage 20 16
set spantree priority 49152 16
Spantree portfast enabled for user ports.
Disabled for trunk ports.
set spantree portfast 2/1-44 enable
set spantree portfast 2/45-50 disable
Spantree port cost is at default.
set spantree portcost 2/49 3004
set spantree portcost 2/50 3004
set spantree portcost 2/1-26,2/28-44 3100
set spantree portcost 2/27,2/45-48 3019
set spantree portpri 2/1-50 32
set spantree portvlanpri 2/1 0
set spantree portvlanpri 2/2 0
set spantree portvlanpri 2/3 0
set spantree portvlanpri 2/4 0
set spantree portvlanpri 2/5 0
set spantree portvlanpri 2/6 0
Port VLAN cost is at default.
set spantree portvlancost 2/1 cost 3099
set spantree portvlancost 2/2 cost 3099
set spantree portvlancost 2/3 cost 3099
set spantree portvlancost 2/4 cost 3099
set spantree portvlancost 2/5 cost 3099
set spantree portvlancost 2/6 cost 3099
set spantree portvlancost 2/7 cost 3099
Spantree is setup on a VLAN and per port/module basis.
Example
Vlan commands at default. If you want to disable spantree
then disable the vlan, ie:
set spantree disable 1 where 1 is the VLAN.
#spantree
#uplinkfast groups
set spantree uplinkfast enable rate 15 all-protocols off
#backbonefast
set spantree backbonefast disable
#vlan 1
set spantree enable 1
set spantree fwddelay 15 1
set spantree hello 2 1
set spantree maxage 20 1
set spantree priority 49152 1
#vlan 16
set spantree enable 16
set spantree fwddelay 15 16
set spantree hello 2 16
set spantree maxage 20 16
set spantree priority 49152 16
Spantree portfast enabled for user ports.
Disabled for trunk ports.
set spantree portfast 2/1-44 enable
set spantree portfast 2/45-50 disable
Spantree port cost is at default.
set spantree portcost 2/49 3004
set spantree portcost 2/50 3004
set spantree portcost 2/1-26,2/28-44 3100
set spantree portcost 2/27,2/45-48 3019
set spantree portpri 2/1-50 32
set spantree portvlanpri 2/1 0
set spantree portvlanpri 2/2 0
set spantree portvlanpri 2/3 0
set spantree portvlanpri 2/4 0
set spantree portvlanpri 2/5 0
set spantree portvlanpri 2/6 0
Port VLAN cost is at default.
set spantree portvlancost 2/1 cost 3099
set spantree portvlancost 2/2 cost 3099
set spantree portvlancost 2/3 cost 3099
set spantree portvlancost 2/4 cost 3099
set spantree portvlancost 2/5 cost 3099
set spantree portvlancost 2/6 cost 3099
set spantree portvlancost 2/7 cost 3099
- Thread starter
- #15
Hi Pete,
I guess this won't get us any further - but as your CLI seems to be a little weird to say the least. how about trying to configure the switch through the Web interface. the commands you need may appear there?
Try enabling the http server and point your browser at the switch IP address.
switch(config)#ip http server
I know it's a long shot, but it may open up some commands that for whatever reason are unavailable through the CLI.
Best o' luck
Phil.
I guess this won't get us any further - but as your CLI seems to be a little weird to say the least. how about trying to configure the switch through the Web interface. the commands you need may appear there?
Try enabling the http server and point your browser at the switch IP address.
switch(config)#ip http server
I know it's a long shot, but it may open up some commands that for whatever reason are unavailable through the CLI.
Best o' luck
Phil.
- Thread starter
- #17
Nice thought Phil, unfortunately the web interface is the same as the CLI it just gives you a box to type the commands instead. Oh and a ping test and a few other diagnostic logs and config reports.
I am really begining to hate this box. Other Cisco's are usually straight forward.
Regards,
Pete
I am really begining to hate this box. Other Cisco's are usually straight forward.
Regards,
Pete
Yup, I never even seen the box and I'm beginning to dislike it a bit too ;-)
Big Stick time I think Pete (?) - there >may< be some of the default layer 2 config still lying around on your switch, negating the spanning tree commands (?). May I suggest, (taking a copy of your config) and then erasing the startup config, reload and try configuring the ports manually as spanning tree portfast.
If successful, try integrating the L3 functions of the switch.
This advice may be a sound as a chocolate teapot - but I'm stumped as to why the switch does not allow you to use commands which every single other cisco switch I've ever seen does so easily.
All the best,
Phil.
Big Stick time I think Pete (?) - there >may< be some of the default layer 2 config still lying around on your switch, negating the spanning tree commands (?). May I suggest, (taking a copy of your config) and then erasing the startup config, reload and try configuring the ports manually as spanning tree portfast.
If successful, try integrating the L3 functions of the switch.
This advice may be a sound as a chocolate teapot - but I'm stumped as to why the switch does not allow you to use commands which every single other cisco switch I've ever seen does so easily.
All the best,
Phil.
- Thread starter
- #19
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Hi,
I am using a Cisco 2948G-L3 switch to break my network into subnets. I am using multiple VLANs and the switch is routing traffic between these VLANs. When I set up a new subnet in order to get it to work I am adding routes to all the servers and workstations outside of the new subnet. How can I get around adding these routes to the systems routing table? Is the Cisco 2948G-L3 the right equiptment to do this routing between subnets.
I am using a Cisco 2948G-L3 switch to break my network into subnets. I am using multiple VLANs and the switch is routing traffic between these VLANs. When I set up a new subnet in order to get it to work I am adding routes to all the servers and workstations outside of the new subnet. How can I get around adding these routes to the systems routing table? Is the Cisco 2948G-L3 the right equiptment to do this routing between subnets.
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