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acl help (dhcp breaks)

Bear with me on this:

here is some of the conifg from a 1710:

interface Ethernet0

ip access-group 102 in

access-list 102 permit udp host eq 53

access-list 102 permit tcp any eq www

access-list 102 deny ip any any log

Ethernet0 is a private connection which is intended to allow guest access to the internet, without any access to the local network. The ACL I applied seems to be working as intended, except for the fact that DHCP will not work to E0. ANy ideas why?

Thanks in advance!

  • Other Network Infrastructure Subjects

Re: acl help (dhcp breaks)

Is the DHCP server on the same net as ethernet0 ?

Are you using IP helper to forward DHCP requests to the DHCP server. ?

If the DHCP server is on a different net and you are using the DHCP relay ( ip helper-address ) feature then add something like this to the acl

permit udp any host eq bootpc

If the DHCP server is on the same net as Ethernet0, then you may want to sniff the traffic going to the DHCP server to find out why it is not providing addresses to the clients.

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