I am actually having an issue with manually assigned IP addresses by a DHCP server on a Cisco 2621XM (12.3.25).
We are actually using a central UNIX DHCP server without any problem since a few years but, for IP Telephony (a Nortel IP phone long story) purposes, I had to move the DHCP server hosting the branch segment to the local router. We actually provide random DHCP addresses to pc's and phones but, we always assign static adresses to printers. It seem that Cisco DHCP has some issue in those cases and, I just wan't an "official confirmation" so I'll stop searching for the solution.
So, here is the situation on a technical point of view.
This is the MAC I see on the printer switch port ..
Vlan Mac Address Type Ports ---- ----------- -------- ----- 49 0014.38dc.324a STATIC Fa0/1
! ip dhcp pool IPDRM0002 host 10.160.49.52 255.255.255.0 client-identifier 0100.1438.dc32.4a (or with hardware-address 0014.38dc.324a) client-name IPDRM0002 lease infinite
It seem that this configuration (with client-identifier) work's fine with a few printers but, I remark that most of them have all different ways to do the DHCPDiscover process. Here what I am getting in the debug for this specific printer ..
Jul 23 09:35:55: DHCPD: DHCPDISCOVER received from client 0000.1438.dc32.4a on interface FastEthernet0/0.49. Jul 23 09:35:57: DHCPD: Sending DHCPOFFER to client 0000.1438.dc32.4a (10.160.49.84). Jul 23 09:35:57: DHCPD: creating ARP entry (10.160.49.84, 0014.38dc.324a). Jul 23 09:35:57: DHCPD: unicasting BOOTREPLY to client 0014.38dc.324a (10.160.49.84). Jul 23 09:35:57: DHCPD: DHCPREQUEST received from client 0000.1438.dc32.4a. Jul 23 09:35:57: DHCPD: Sending DHCPACK to client 0000.1438.dc32.4a (10.160.49.84). Jul 23 09:35:57: DHCPD: creating ARP entry (10.160.49.84, 0014.38dc.324a). Jul 23 09:35:57: DHCPD: unicasting BOOTREPLY to client 0014.38dc.324a (10.160.49.84).
It seem that some devices send a media-type before the mac-address and some don't. Also, they can put 01 as ethernet media-type and 00 (for this specific case) wich is ... no idea ...
I searched on many forums and, found this thread where someguy have the exact same issue than me.
Here's the easiest way to do your manual bindings.
1. on your DHCP server, turn on:
ip dhcp server events debug ip dhcp server packet
2. reboot your printer and watch its DHCP (or possibly BOOTP) request come in
3. issue the command "show ip dhcp binding"
If the printer got the manual binding, then that's great. If it got an address from the pool instead, then use its client ID / hardware address instead.
Note: if "show ip dhcp binding" shows the "hardware address" in MAC address format, a la 0001.e667.92ad, then use that as hardware-address rather than as client-identifier. If binding shows some other format, then that's a client-identifier.
Our documentation on this could use some work I'm afraid.
The DHCP reply to the client using the media-type and, create a APR entry without it but, why do I need to debug just to be able to assign an IP address. Unix just don't care about the media-type and, assign the address using the MAC address only.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.