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New Member

Vlans unable to access internet


I have a 3750 switch ,created the vlans and working fine. i have a ISA sever which is in SERVER VLAN.

if i give the default gateway of SERVER VLAN in ISA server the clients can't able to access the internet. but,it is able to access the files in the ISA server.

If i remove the default gateway address of the SERVER VLAN from the ISA server, i am able to access the internet on ISA server.but, the client cann't contact the ISA server b'cause the vlan gateway is taken.

so,i want other vlans to access the internet by using ISA sever.

Plz help me to sort out this issue.Thx in advance....


1. I have SERVER VLAN,VLAN1 and VLAN2. inter vlan is done. i am able to access the servers in SERVER VLAN from other vlan.

2. The ISA server has two NIC connected to the public network and other to private.and routing is done b'ween the two.

New Member

Re: Vlans unable to access internet

Could you use a static route to force them to go to the server?

ip route



New Member

Re: Vlans unable to access internet


The ISA server is providing a "NAT" or "Proxy" service to the hosts that are to route through it?

Can the ISA server access the Internet?

Are there any logs to review on the ISA server for failed connectivity?



New Member

Re: Vlans unable to access internet

You need a static route from your ISA server to the SERVER VLAN default gateway for your internal networks. You didn't specify your internal address scheme, but say you are using /24, /24 and /24. Your ISA server is and the default gateway for that VLAN is You would need to add the following routes from your windows command prompt:

route add mask

If the routes can't be summarized like that you would need a similar line for each network.