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no DHCP when applying access list

Addey Salameh
Level 1
Level 1
2 Accepted Solutions

Accepted Solutions

Add the following line to your ACL and DHCP should work:

ip access-list extended Block_Facebook
  1 permit udp any eq bootpc any eq bootps

View solution in original post

Hi,

You blocked DHCP discover packet with your current ACL, Discover packet has sender IP of 0.0.0.0 (port 68) and destination IP of 255.255.255.255 (port67) which is being blocked by this ACL. Adding line 

 permit udp any eq 68 host 255.255.255.255 eq 67

 

can solve your problem. (There are other possibilities for allow DHCP in ACLs)

 

Anyway, why u did not use "name-server" to simplify ur ACL with only 1 line to block facebook?

 

HTH,

Houtan

View solution in original post

3 Replies 3

Add the following line to your ACL and DHCP should work:

ip access-list extended Block_Facebook
  1 permit udp any eq bootpc any eq bootps

Thank You guys you helped me alot :D

 

Hi,

You blocked DHCP discover packet with your current ACL, Discover packet has sender IP of 0.0.0.0 (port 68) and destination IP of 255.255.255.255 (port67) which is being blocked by this ACL. Adding line 

 permit udp any eq 68 host 255.255.255.255 eq 67

 

can solve your problem. (There are other possibilities for allow DHCP in ACLs)

 

Anyway, why u did not use "name-server" to simplify ur ACL with only 1 line to block facebook?

 

HTH,

Houtan

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