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Manual DHCP binding static-dynamic on 3750

Hi NG,

i'm currently stuck on following, i try to create a dhcp scope on one of my WS-C3750Gs. The global scope should begin at .16 and end at .199. within this scope i have deliver single ip adresses static-dynamicly via dhcp.dhcp works fine for the rest, but those i want to deliver static-dynamicly newer use there configured reservation. my config is according to the IOS IP Configuration Guide. as follows:

ip dhcp excluded-address 10.10.10.0 10.10.10.15 ip dhcp excluded-address 10.10.10.200 10.9.8.255 ! ip dhcp pool students network 10.10.10.0 255.255.255.0 domain-name my.domain.xy dns-server IP_of_NS1 IP_of_NS2 default-router 10.10.10.1 lease 0 8 40 ! ip dhcp pool COMPUTER_1 host 10.10.10.35 255.255.255.0 hardware-address XXXX.YYYY.ZZZZ client-name COMPUTER_1

any suggestions are welcome. thank you, cheers colin

Reply to
colin c.
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you miss the OS identifier of the client

debug dhcp will tell you whats wrong

HTH Martin

Reply to
Martin Bilgrav

fx use client-identifier 0100.4063.d67b.4a and not hardware-address XXXX.YYYY.ZZZZ

Reply to
Martin Bilgrav

"Martin Bilgrav" schrieb im Newsbeitrag news:9XoEg.104$ snipped-for-privacy@news.getnet.dk...

so i basicly just have to swop hardware with the client-identifier thats it. well ok gona try it tomorrow right away. hey martin, youre rather a speedy! the answer just came within 2 minutes wow!

Reply to
colin c.

i.e. if your hw address is

XXXX.YYYY.ZZZZ

use

01XX.XXYY.YYZZ.ZZ

Thats Zero One

ip dhcp pool 3 host 172.19.16.201 255.255.255.0 client-identifier 0100.166f.0370.02

My hw address is 0016.6f03.7002

Reply to
Bod43

schrieb im Newsbeitrag news: snipped-for-privacy@m73g2000cwd.googlegroups.com...

whats about the 01 prefix part? what does it define?

Reply to
colin c.

I don't know. I needed to get this working one day and hacked about until it did.

Please post when you find out.

If Aaron is listening, maybe the docs need a bit of tidying here? This took me several hours to get working a while back. That little magic 01 and the left justified dots took quite a bit of figuring out. (I initially tried right justified dots 01.xxxx.xxxx.xxxx since that seemed the best thing to do). As can be seen above a fully worked example is only a few of lines long. It was also not clear to me from the docs how the static reservations interacted with dynamic pools and I had to do experiments to find out.

End of rant:-)

Reply to
Bod43

schrieb im Newsbeitrag news: snipped-for-privacy@h48g2000cwc.googlegroups.com...

Thank you for saving us from hours of reserch!! I hope this post will be precius to others.

Reply to
colin c.

I recently run into this problem, and my understanding is that the 01 prefix defines that the rest of the client identifier (i.e. the MAC address) is from an Ethernet connection.

However, an interesting fact that came up, but isn't covered very well, is that 'hardware-address' and 'client-identifier' are for BOOTP and DHCP receptively. DHCP will ignore the former, requiring that you use the latter.

Reply to
Jonathan Wright

Not quite. From RFC2131:

A DHCP server needs to use some unique identifier to associate a client with its lease. The client MAY choose to explicitly provide the identifier through the 'client identifier' option. If the client supplies a 'client identifier', the client MUST use the same 'client identifier' in all subsequent messages, and the server MUST use that identifier to identify the client. If the client does not provide a 'client identifier' option, the server MUST use the contents of the 'chaddr' field to identify the client.

Reply to
Martin Gallagher

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