Routing on 3750

Unanswered Question
Oct 25th, 2007
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I have one 3750 switch and i intend to use this as an edge router as well as access switch. I can't sem to get it to work. I configured a port with NO SWITCHPORT and assigned apublic IP to it, IP DEFAULT_GATEWAY was also configured. I am able to ping outside addresses from the swith. How can i get inside hosts to access the internet then.

Secondly, how is INTER-VLAN rounting configured on one 3750 switch without an external router?



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Overall Rating: 4 (2 ratings)
spremkumar Thu, 10/25/2007 - 01:02
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Can you revert back on the ip addresing scheme being used in your network over there ?

can you also post the config of your switch over here ?

you just need to have ip routing command configured in your switch to have inter vlan routing function...


ankbhasi Thu, 10/25/2007 - 01:18
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Hi Toyin,

For intervlan routing you have to configure vlan interface which are layer 3 logical interface and then assign them an ip address and further your clients who belong to that vlan should have the gateway address as what you have configured on vlan interface on switch and once enbale "ip routing" on global config mode you are done with intervlan routing.

Something like this

interface vlan x

ip address

Now this ip address should be assigned as a gateway address for client in those respective vlans.

NOTE:3750 does not support NAT so your clients on lan cannot hit internet with private ip address.



*Pls rate all helpfull post

toyinsekoni Thu, 10/25/2007 - 06:15
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Thanks guys. ip routing sure did. I actually had ip default-gateway set, and with the ip rounting command, i could/can no longer ping the default gateway thru the L3 port.

Is it possible to do dhcp with VLAN. I have the 4 vlans where the host should use DHCP. How do i do dhcp for each vlan host and at the same time route the hosts to the internet through a PIX/Router?



amolak_cisco Thu, 10/25/2007 - 08:49
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You can configure the vlan as follows:

int vlan XX

ip helper-address

You need to create 4 network pools on the DHCP server according to the 4 vlan network ranges.

For example:

vlan1 -

vlan2 -

vlan3 -

vlan4 -

DHCP server IP address -

int vlan1

ip address

ip helper-address

int vlan2

ip address

ip helper-address

int vlan3

ip address

ip helper-address

int vlan4

ip address

ip helper-address

ip routing

ip route

Hope this helps.



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