07-02-2012 08:18 AM - edited 03-07-2019 07:34 AM
We have confirmed all internal traffic trying to access the internet getting to the Cisco 3750 stack but nothing leaving going through external interface to the internet.
We have an MPLS router with external interface configured with static Ip and able to ping the internet 4.2.2.2, we have an interface fa0/0/0 directly connected to the Cisco 3750 switch and both passing traffic. when our users try to use the internet traffic hits the 3750 stack but not able to use the internet. I'm trying to ping 4.2.2.2 from my 3750 stack and not able to and not sure why, as I'm able to pint the external interface on the MPLS routing that connects to the internet
I need your help as what is the problem.
Thank you
Solved! Go to Solution.
07-02-2012 09:59 AM
the ip default-gateway command u set up there, is for times that u consider ur switches to act as a HOST. in other words; routing disabled, it just sends the local traffic to a gateway. it doesnt do routing. the ip route u just set does the routing.
HTH,
plz Rate if it helped.
Soroush.
07-02-2012 08:30 AM
Hi,
if your hosts are setup with a default gateway, then I think you havent set proper routing in ur network. does your stack works in layer 3?
pingin external interface in ur own network from the switch doesnt mean u have correct setup.
HTH,
Soroush.
07-02-2012 08:40 AM
I'm on my Cisco 3750 stack trying to ping google.com at 4.2.2.2 through my default gayteway the MPLS router and no replay, we have IP routing setup on the 3750 stack - ping will not work or connect to the inter.
Thanks
07-02-2012 08:48 AM
does your cisco 3750 works at layer 3? what's the ip address of the F0/0/0 on MPLS router? is this set as your default gateway?
HTH,
Soroush.
07-02-2012 08:48 AM
Can you post "sh run" from the 3750?
07-02-2012 09:09 AM
The sh ru
Current configuration : 21545 bytes
!
version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname AIKENDRSW00
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$xwGc$3jmMu8cGriv2.cgwezyS7.
enable password 7 04585B0829604B5B1B4A
!
!
!
no aaa new-model
clock timezone EST -5
switch 1 provision ws-c3750g-48ps
switch 2 provision ws-c3750g-48ps
switch 3 provision ws-c3750g-48ps
system mtu routing 1500
ip routing
spanning-tree mode pvst
spanning-tree extend system-id
spanning-tree vlan 110,120 priority 4096
!
vlan internal allocation policy ascending
interface GigabitEthernet3/0/48
switchport access vlan 555
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet3/0/49
!
interface GigabitEthernet3/0/50
!
interface GigabitEthernet3/0/51
!
interface GigabitEthernet3/0/52
!
interface Vlan1
ip address 10.1.2.1 255.255.255.0
!
interface Vlan2
description dr vmotion
no ip address
!
interface Vlan3
ip address 172.16.3.1 255.255.255.0
!
interface Vlan4
description dr vmotion
no ip address
!
interface Vlan5
description <**Aiken_DR_192.168.10_Network**>
ip address 192.168.10.2 255.255.255.0
!
interface Vlan110
ip address 10.10.10.254 255.255.255.0
!
interface Vlan120
ip address 10.10.20.254 255.255.255.0
!
interface Vlan140
ip address 10.10.40.254 255.255.255.0
!
interface Vlan172
no ip address
!
interface Vlan173
ip address 172.16.10.3 255.255.255.0
interface Vlan174
ip address 172.16.20.3 255.255.255.0
!
interface Vlan555
description Aiken_Internet
ip address 184.95.133.254 255.255.255.0
!
ip default-gateway 184.95.133.1
ip classless
ip route 10.1.1.0 255.255.255.0 10.1.2.42
ip route 10.10.1.0 255.255.255.0 10.1.2.42
ip route 10.10.2.0 255.255.255.0 10.1.2.42
ip route 10.10.4.0 255.255.255.0 10.1.2.42
ip route 172.16.1.0 255.255.255.0 10.1.2.42
ip route 192.168.0.0 255.255.255.0 10.1.2.42
ip http server
ip http secure-server
!
ip sla enable reaction-alerts
!
Current configuration : 21545 bytes
!
version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname AIKENDRSW00
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$xwGc$3jmMu8cGriv2.cgwezyS7.
enable password 7 04585B0829604B5B1B4A
!
!
!
no aaa new-model
clock timezone EST -5
switch 1 provision ws-c3750g-48ps
switch 2 provision ws-c3750g-48ps
switch 3 provision ws-c3750g-48ps
system mtu routing 1500
ip routing
spanning-tree mode pvst
spanning-tree extend system-id
spanning-tree vlan 110,120 priority 4096
!
vlan internal allocation policy ascending
All interfaces here
then
interface GigabitEthernet3/0/48
switchport access vlan 555
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet3/0/49
!
interface GigabitEthernet3/0/50
!
interface GigabitEthernet3/0/51
!
interface GigabitEthernet3/0/52
!
interface Vlan1
ip address 10.1.2.1 255.255.255.0
!
interface Vlan2
description dr vmotion
no ip address
!
interface Vlan3
ip address 172.16.3.1 255.255.255.0
!
interface Vlan4
description dr vmotion
no ip address
!
interface Vlan5
description <**Aiken_DR_192.168.10_Network**>
ip address 192.168.10.2 255.255.255.0
!
interface Vlan110
ip address 10.10.10.254 255.255.255.0
!
interface Vlan120
ip address 10.10.20.254 255.255.255.0
!
interface Vlan140
ip address 10.10.40.254 255.255.255.0
!
interface Vlan172
no ip address
!
interface Vlan173
ip address 172.16.10.3 255.255.255.0
interface Vlan174
ip address 172.16.20.3 255.255.255.0
!
interface Vlan555
description Aiken_Internet
ip address 184.95.133.254 255.255.255.0
!
ip default-gateway 184.95.133.1
ip classless
ip route 10.1.1.0 255.255.255.0 10.1.2.42
ip route 10.10.1.0 255.255.255.0 10.1.2.42
ip route 10.10.2.0 255.255.255.0 10.1.2.42
ip route 10.10.4.0 255.255.255.0 10.1.2.42
ip route 172.16.1.0 255.255.255.0 10.1.2.42
ip route 192.168.0.0 255.255.255.0 10.1.2.42
ip http server
ip http secure-server
!
ip sla enable reaction-alerts
!
IP default-gateway is the MPLS external interface - able to ping the external IP from 3750 switch
07-02-2012 09:29 AM
EDIT:
Look, the default gateway here u set is not what takes the internet traffic from hosts to the gateway router. for internet traffic to go to router and out, u have to set a default route using ip route. that is if there is a traffic comming in which ur switch doesnt know where to send it, it sends it to the mpls router. that will include traffic from hosts to internet.
Hope it Helps,
Soroush.
07-02-2012 09:38 AM
I"m trying to figure this out so I added this route IP route 0.0.0.0 0.0.0.0 x.x.x.x the X is the external interface on the MPLS router and all works now, can someone tell me why the default gateway being set to the external IP address is not enough
Thanks
07-02-2012 09:59 AM
the ip default-gateway command u set up there, is for times that u consider ur switches to act as a HOST. in other words; routing disabled, it just sends the local traffic to a gateway. it doesnt do routing. the ip route u just set does the routing.
HTH,
plz Rate if it helped.
Soroush.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide