12-16-2007 10:44 AM - edited 03-05-2019 08:01 PM
hi all,
just want to post a situation here. i have 2 catalyst 4908G (8-port) with
bridging enabled. it was configured to run as redundant switch router for vlan
with port #8 configured as etherchannel connected to port #8 of the second switch
with port-channel subinterface and encapsulation configured as well.
everything works fine until the second switch fails.
we replaced the second switch with catalyst 3750G (12 port). the bridging was
configured and port #12 was assigned to connect to port #8 of the catalyst 4908G
but unfortunately i cannot ping the ip address of the bridge of the catalyst 3750 from
our network neither i can ping the ip address of the bridge of catalyst 4908G from the console
of the 3750 switch. what seems to be the problem?
all interfaces were verified as up and running.
the following are the configuration of the bridge and etherchannel of the 2 switches:
catalyst 4908G:
interface port-channel1
no ip address
no ip directed-broadcast
hold-queue 300 in
!
interface port-channel1.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
---output cut
!
interface GigabitEthernet8
no ip address
no ip directed broadcast
channel-group 1
!
interface Bvi1
ip address 172.25.x.x netmask
ip helper-address 172.25.a.b
no ip redirects
no ip directed-broadcast
standby 1 priority 105 preempt
standby 1 ip 172.25.1.1
---output cut
catalyst 3750
!
interface port-channel1
hold-queue 300 in
---output cut
!
interface GigabitEthernet12
channel-group 1 on
!
interface Bvi1
ip address 172.25.x.y netmask
no ip route-cache cef
standby 1 preempt
standby 1 ip 172.25.1.1
!
---output cut
12-16-2007 10:55 AM
Any reason why are you bridging ? The switch bridges by default, no need to use BVI.
This configuration would be useful when you have a router and you want this router to behave like a switch.
I also don't see the need for etherchanneling on a single link. Etherchanneling is used when you want to bundle 2 or more links for bandwidth aggregation and/or faul tolerance.
Your configuration should be as follow:
catalyst 4908G:
interface GigabitEthernet8
switchport trunk encapsulation dot1q
switchport mode trunk
interface vlan 1
ip address 172.25.x.x netmask
ip helper-address 172.25.a.b
no ip redirects
no ip directed-broadcast
standby 1 priority 105 preempt
standby 1 ip 172.25.1.1
catalyst 3750
interface GigabitEthernet12
switchport trunk encapsulation dot1q
switchport mode trunk
interface vlan 1
ip address 172.25.x.y netmask
standby 1 preempt
standby 1 ip 172.25.1.1
!
12-16-2007 11:31 AM
thank you for your quick response mr. EdisonOrtiz. i do have a router. basically the function of those 2 switches is to work redundantly if either of them fails one of them will be up and running. i've tried to shut down the first switch (4908G) to see if the second switch (3750) will provide the network connectivity but it fails. i cannot ping any ip address in the network. do you think the trunking from 4908G to 3750G will resolve the problem in the 3750G switch?
12-16-2007 11:50 AM
thank you for your quick response mr. EdisonOrtiz. i do have a router. the reason i used bridge is to group all subinterfaces that i configured for vlan trunk. basically the function of those 2 switches is to work redundantly(STP)if either of them fails one of them will be up and running. i've tried to shut down the first switch (4908G) to see if the second switch (3750) will provide the network connectivity but it fails. i cannot ping any ip address in the network. do you think the trunking from 4908G to 3750G will resolve the problem in the 3750G switch?
12-16-2007 12:56 PM
I meant, the BVI configuration will be on a router, not that you need BVI if you have a router in the topology.
Please follow my suggestions to make this work.
01-03-2008 11:48 AM
Sir EdisonOrtiz,
How are you Sir? I tried the configuration that you gave me but the problem is that 4908G switch was not recognized switchport command thus I cannot make the interface as trunk. So still i cannot connect to my 3750 switch. By the way the reason for BVI configuration was for routing. and for you to have a better feel of our switch configuration below is the configuration for both 4908G and 3750 switch. note: 4908G switch is the active.
4908G-L3 config:
bridge irb
!
!
!
interface Port-channel1
no ip address
no ip directed-broadcast
hold-queue 300 in
!
interface Port-channel1.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet1
no ip address
no ip directed-broadcast
!
interface GigabitEthernet1.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet1.10
encapsulation isl 10
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 10 priority 105 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet2
no ip address
no ip directed-broadcast
!
interface GigabitEthernet2.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet2.20
encapsulation isl 20
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 20 priority 105 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet3
no ip address
no ip directed-broadcast
!
interface GigabitEthernet3.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet3.30
encapsulation isl 30
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 30 priority 105 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet4
no ip address
no ip directed-broadcast
!
interface GigabitEthernet4.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet4.40
encapsulation isl 40
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 40 priority 105 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet5
no ip address
no ip directed-broadcast
!
interface GigabitEthernet5.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet5.50
encapsulation isl 50
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 50 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet6
no ip address
no ip directed-broadcast
!
interface GigabitEthernet6.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet6.60
encapsulation isl 60
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 60 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet7
no ip address
no ip directed-broadcast
!
interface GigabitEthernet7.1
encapsulation isl 1
no ip redirects
no ip directed-broadcast
bridge-group 1
!
interface GigabitEthernet7.70
encapsulation isl 70
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 70 preempt
standby 1 ip 172.25.f.g
!
interface GigabitEthernet8
no ip address
no ip directed-broadcast
channel-group 1
!
interface BVI1
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip redirects
no ip directed-broadcast
standby 1 priority 105 preempt
standby 1 ip 172.25.f.g
!
router eigrp 200
network 172.25.0.0
no auto-summary
!
ip classless
ip route 0.0.0.0 0.0.0.0 172.25.d.e
!
bridge 1 protocol ieee
bridge 1 route ip
!
end
3750 switch config:
bridge irb
!
interface Port-channel1
hold-queue 300 in
!
interface GigabitEthernet1/0/1
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 10 ip 172.25.f.g
standby 10 preempt
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/2
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 20 ip 172.25.f.g
standby 20 preempt
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/3
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 30 ip 172.25.f.g
standby 30 preempt
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/4
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 40 ip 172.25.f.g
standby 40 preempt
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/5
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 50 ip 172.25.f.g
standby 50 preempt
standby 50 priority 105
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/6
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 60 ip 172.25.f.g
standby 60 preempt
standby 60 priority 105
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/7
no switchport
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
standby 70 ip 172.25.f.g
standby 70 preempt
standby 70 priority 105
bridge-group 1
no shutdown
!
interface GigabitEthernet1/0/8
!
interface GigabitEthernet1/0/9
!
interface GigabitEthernet1/0/10
!
interface GigabitEthernet1/0/11
!
interface GigabitEthernet1/0/12
channel-group 1 mode on
no shutdown
!
interface BVI1
ip address 172.25.x.y 255.255.b.z
ip helper-address 172.25.a.a
no ip route-cache cef
standby 1 preempt
standby 1 ip 172.25.f.g
!
exit
!
bridge 1 protocol vlan-bridge
bridge 1 route ip
!
ip routing
router eigrp 200
network 172.25.0.0
no auto-summary
!
exit
!
ip classless
ip route 0.0.0.0 0.0.0.0 172.25.d.e
!
end
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