Cisco IOS Command Question - bootpc?

red24698
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I need to know what this Cisco IOS command means and what it does.  It is usually listed in an acl I think:

permit udp any any eq bootpc

Thanks for your help.
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It's the Bootstrap Protocol Client. It's related to the IP helper service for forwarding DHCP requests from other subnets to the one that has your DHCP server. This ACL permits UDP bootstrap protocol client (bootpc) packets from any source to any destination. This ACL is used by Unicast Reverse Path Forwarding on Internet-facing router interfaces.

http://en.wikipedia.org/wiki/Bootstrap_Protocol
http://slaptijack.com/networking/ciscos-ip-helper-address-too-forward/

Commented:
it means: allow any host from any source to any destination
and the allowed protocol in your case is the boot protocol client UDP port68 bootpc

so If you have any clients configured to obtain an IP address automatically from a DHCP server they will send a packet called a DHCP discovery packet out on the network. This packet identifies that a client is searching for an IP address. The packet uses UDP port 68 as it's source address for the client, since it does not have an IP address that refers back to the client.

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