freebsd stable - Jun 2007 - Server setup as a Diskless Server on reboot sends DHCP Discover packets out

Hey Guys,

I have a strange one:

I've setup a machine as a diskless server, using PXEBoot with ihc-dhcpd
to offer dhcp and dhcp configuration information. I did a test reboot on
the server, and found to my dismay that the server NIC's are sending out
dhcp discover packets and trying to get an address.

The NIC's IP info is captured correctly in /etc/rc.conf:

<snip>
ifconfig_bge0="inet 196.30.157.162 media 100baseTX mediaopt full-duplex
netmask 255.255.255.192"
ifconfig_bge1="inet 196.31.157.162 media 100baseTX mediaopt full-duplex
netmask 255.255.255.0"
<snip>

and the /etc/dhclient.conf file is empty. I thought maybe it was the
/conf directory used in the diskless Root structure creation, so I
renamed it out of the way, but that made no difference.

I can't seem to find where the definition is that makes the NIC's ask
for DHCP info.
 
Shortened output of /var/run/dmesg.boot pertaining to the DHCP Discover
packets:

<snip>
Sending DHCP Discover packet from interface bge0 (00:0b:db:e6:a9:33)
Sending DHCP Discover packet from interface bge1 (00:0b:db:e6:a9:35)
DHCP/BOOTP timeout for server 255.255.255.255
DHCP/BOOTP timeout for server 255.255.255.255
DHCP/BOOTP timeout for server 255.255.255.255
DHCP/BOOTP timeout for server 255.255.255.255
DHCP/BOOTP timeout for server 255.255.255.255
Received DHCP Offer packet on bge0 from 196.30.157.161 (accepted) (no
root path)
Sending DHCP Request packet from interface bge0 (00:0b:db:e6:a9:33)
DHCP/BOOTP timeout for server 255.255.255.255
Received DHCP Ack packet on bge0 from 196.30.157.161 (accepted) (got
root path)
DHCP timeout for interface bge1
bge0 at 196.30.157.149 server 196.30.157.161 server name
diskless.csc.jnb6.za.uu.net boot file pxeboot
subnet mask 255.255.255.192 router 196.30.157.129 rootfs
196.30.157.161:/diskless_root
Adjusted interface bge0
Shutdown interface bge1
Trying to mount root from ufs:/dev/aacd0s1a
<snip>

9 times out of ten the DHCP will just sit and timeout (it gets a DHCP
return from my other diskless server running DHCPD) and then the 1 time
out of 10 will mount the hard drive / partition.

Thanks

Kim Attree

Kim Attree wrote:
 > I've setup a machine as a diskless server, using PXEBoot with
ihc-dhcpd
 > to offer dhcp and dhcp configuration information. I did a test reboot on
 > the server, and found to my dismay that the server NIC's are sending
out
 > dhcp discover packets and trying to get an address.
 > 
 > The NIC's IP info is captured correctly in /etc/rc.conf:
 > [...]
 > and the /etc/dhclient.conf file is empty. I thought maybe it was the
 > /conf directory used in the diskless Root structure creation, so I
 > renamed it out of the way, but that made no difference.
 > 
 > I can't seem to find where the definition is that makes the NIC's
ask
 > for DHCP info.
 >  
 > Shortened output of /var/run/dmesg.boot pertaining to the DHCP Discover
 > packets:
 > 
 > <snip>
 > Sending DHCP Discover packet from interface bge0 (00:0b:db:e6:a9:33)
 > Sending DHCP Discover packet from interface bge1 (00:0b:db:e6:a9:35)

That's the kernel itself trying to perform BOOTP/DHCP.
It does that before mounting the root file system (which
might be mounted via NFS anyway, requiring an IP address
to be obtained via BOOTP or DHCP).

If you don't want that, then remove "options BOOTP" from
your kernel config file and rebuild your kernel.

Best regards
   Oliver

-- 
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