Do keep in mind that even with a ping check, certain client devices (especially Microsoft with firewall enabled) will not respond to an ICMP echo packet, thus leading the DHCP server to infer that an address is available when, technically, it is not… and thus leading to duplicate address error messages as well. It’s one of those pains that we just have to learn to work around.
Rgds,
Ron
--
Ron Marosko, Jr.
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Global Technology Resources,Inc.
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From: [email protected]
[mailto:[email protected]] On Behalf Of Michael Ruetz
Sent: Wednesday, January 08, 2014 10:32 AM
To: Jeff Rensink; Justin Kurynny
Cc: [email protected]
Subject: Re: [OSL | CCIE_Wireless] DHCP on IIOS
Hi again,
Thx. to both of you, solution one was my favorite too. :)
The PING-check you (Jeff) mentioned is new to me (as so much other stuff),
sounds interesting.
Greetings from Austria …
MICHAEL RUETZ
Senior IT Architekt/Engineering Manager, CCIE#5356 R/S
Von: Jeff Rensink <[email protected]<mailto:[email protected]>>
Datum: Mittwoch, 08. Jänner 2014 17:08
An: Justin Kurynny <[email protected]<mailto:[email protected]>>
Cc: Michael Ruetz <[email protected]<mailto:[email protected]>>,
"[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>
Betreff: Re: [OSL | CCIE_Wireless] DHCP on IIOS
I agree with Justin. The switches will do a check (I'm guessing it's a ping)
before handing out an IP address. But why run the risk of an accidental
duplicate address.
Regards,
Jeff Rensink : Sr Instructor : iPexpert<http://www.ipexpert.com/>
CCIE # 24834 :: Wireless / R&S
:: World-Class Cisco Certification Training
Direct: +1.810.326.1444
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On Wed, Jan 8, 2014 at 12:17 AM, Justin Kurynny
<[email protected]<mailto:[email protected]>> wrote:
Michael,
I’d personally go with the first option unless otherwise instructed by the
exam. You know that in real life you probably wouldn’t do it the second way,
especially considering conflicts could occur (yes, I know the lab isn’t real
life). The argument here is that I don’t like to leave anything to chance in
the lab and you don’t want to be troubleshooting a self-inflicted DHCP/IP
conflict issue on top of everything else you’re already doing.
It’s slightly more configuration work, but because IOS doesn’t offer a DHCP
clustering/LB mechanism, I’d just split the pools.
Justin
From:[email protected]<mailto:[email protected]>
[mailto:[email protected]<mailto:[email protected]>]
On Behalf Of Michael Ruetz
Sent: Tuesday, January 07, 2014 21:45
To: [email protected]<mailto:[email protected]>
Subject: [OSL | CCIE_Wireless] DHCP on IIOS
Dear Wireless-Guys,
I though about setting up a redundant DHCP-Service running on two IOS-Devices
while preparing for the lab (in march), and came up with two solutions:
— split the DHCP-pools in half on the two boxes
— configure both devices with the same (!) pool of addresses, and leave it to
the client’s duplicate-adress-check to resolve any issues
Any recommendations from your side would be very welcome.
Best regards …
MICHAEL RUETZ
Senior IT Architekt/Engineering Manager, CCIE#5356
_______________________________________________
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________________________________
This message contains confidential information and is intended only for the
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