[hpsdr] Metis and DHCP and LinkSys Routers

[Phil Harman]

Hi Roger,

Thanks the feedback.

On of the issues I found when developing the DHCP code for Meits was that 
there are a number of 'options' that may be used.

I found that some of these were actually 'essentials' and others caused the 
DHCP process to fail.  The options currently used were  found by trial and 
error and worked for the Beta testers.

If you could do a WireShark capture of your PC negotiating a successful DHPC 
exchange with your LinkSys router I can perhaps see which options are being 
used.

If folks are finding that the APIPA assignment is taking too long then you 
may want to consider assigning a fix IP address to Metis.

73 Phil...VK6APH


----- Original Message ----- 
From: "w3sz" <73w3sz at gmail.com>
To: <hpsdr at openhpsdr.org>; "Roger Rehr" <73w3sz at gmail.com>
Sent: Sunday, March 06, 2011 8:37 AM
Subject: [hpsdr] Metis and DHCP and LinkSys Routers


> ***** High Performance Software Defined Radio Discussion List *****
>
> Just a note for those who may be seeing 'funny things' in terms of IP 
> address assignment when starting Metis.
> At my QTH I use only 'true' switches on the LAN.
> I have a LinkSys BEFSR11 Router that is the DHCP server for my network 
> (assigning IP addresses to my wife's and daughters' fixed and portable 
> devices; my computers all have fixed IP addresses).
> I found that Metis would not successfully get an IP address from the 
> Router.  The Router and Metis would exchange a round of 2 
> Discover-Offer-Request-NAK sequences and then Metis would get an APIPA 
> address.  Metis works fine with that.
>
> I decided to see if setting up a DHCP server on my Linux mailserver would 
> provide a DHCP server that would succeed in giving Metis an IP address.  I 
> found that just activating the DHCP server on the Linux box would allow 
> the LinkSys Router to give Metis an IP address.  I know that the IP 
> address was coming from the Router and not the Linux box DHCP server 
> because [1] I limited the Linux box to addresses between 192.168.1.200 and 
> .229 and the Metis IP address assigned was 192.168.1.104 (or other .10x 
> addresses), and [2] by reviewing the WireShark output..
>
> If I disconnected the Router from the switch that had my Linux mailserver, 
> Metis, and my Windows PC-with-Wireshark, then the Linux DHCP server would 
> also successfully give Metis an IP address [in the .200 to .229 range]. 
> But if both DHCP servers were available, the LinkSys Router would prevail.
>
> I just pass this along as info to anyone who may be having trouble getting 
> an IP address from their Linksys Router...not that you need to do so, 
> since Metis will give itself an APIPA address if the DHCP assignment 
> fails.
>
> I have confirmed this behavior several times by turning off the DHCP 
> server on the Linux box and again seeing the LinkSys Router fail to assign 
> an IP address to Metis, and turning back on the DHCP server on the Linux 
> box and having the LinkSys Router then again suceed in giving an IP 
> address to Metis.
>
> I have also duplicated the behavior with 2 separate Metis cards.  Both 
> have the original firmware; I have not attempted to load new firmware.
>
> I got the same behavior whether I connected Metis to the switch to which 
> the LinkSys Router is connected, or to the branch switch that has my 
> Windows PC and the Linux mailserver.
>
> Interestingly, the LinkSys Router seems to do fine assigning IP addresses 
> to the PCs on the network that don't have fixed IP addresses, even in the 
> absence of the Linux box DHCP server.  So this is not a general problem 
> with my LinkSys Router's DHCP function.
>
> I do not have an explanation for this behavior, and this is definitely not 
> a complaint or even a bug report, but just information for anyone who may 
> have noticed that their LinkSys Router wouldn't successfully give Metis an 
> IP address.  It really doesn't matter to me if my Metis has the IP 
> 192.168.1.x or 169.254.x.x. So I am quite happy with things as they are 
> ;)
>
> -- 
> 73,
>
> W3SZ
> Roger Rehr
> http://www.nitehawk.com/w3sz
>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help: 
> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 10.0.1204 / Virus Database: 1435/3482 - Release Date: 03/04/11
> 


 1299380466.0