[K12OSN] DHCP and different LTSP distros

[John Lucas]

On Tuesday 10 July 2007 22:35, Krsnendu dasa wrote:
> On 29/06/07, William Fragakis <william at fragakis.com> wrote:
> > Tweaks for servers serving older PCs:
> > If the PC, while PXE booting fails to get further than grabbing an IP
> > address or begin tftp, you likely an older PXE firmware (0.99) that
> > requires certain tweaks. Newer clients do not require these steps but it
> > doesn't hurt to do them to facilitate easy swapping of clients later.
> > We've only found this to be an issue with PII 350 and 400 Compaq
> > DeskPros.
> > Open the computer -> filesystem -> /etc
> >
> > open file /etc/sysctl.conf (it should open with Gedit or Kedit) append
> > the file with the following (Include the # sign! It denotes a comment
> > which is for human eyes and for the server to ignore. Well commented
> > files make things easy for those who follow you.)
> >
> > # Disable MTU discovery for older PXE NICs (0.99)
> > net.ipv4.ip_no_pmtu_disc = 1
> >
> > save the file and close
> >
> > next, open file /etc/xinetd.d/tftp
> >
> > change this line:
> > server.args = -s /tftpboot
> >
> > to:
> > server.args = -r blksize -s /tftpboot
> >
> > save the file and close (essentially, you are adding the -r blksize
> > parameter). This change unlike any others will not be effective until
> > you reboot the server. This is the only change that requires a reboot
> > since it is kernel level. All other changes are package or service level
> > and only require restarting that application or service.
>
> I tried these settings, and now I get this message from tail -f
> /var/log/messages when I start dhcpd and none of the clients can boot
> from this server. Wen I start dhcpd on the secondary server the
> terminals are able to boot from there.
>
> Jul 11 14:27:36 k12ltsp2 dhcpd: Failover CONNECT from 192.168.0.253:
> time offset too large
> Jul 11 14:27:36 k12ltsp2 dhcpd: failover: disconnect: time offset too large
> Jul 11 14:27:36 k12ltsp2 dhcpd: dhcpd startup succeeded
> Jul 11 14:27:51 k12ltsp2 dhcpd: failover peer ltsp: I move from
> startup to communications-interrupted
> Jul 11 14:27:51 k12ltsp2 dhcpd: failover: link startup timeout
>

Are your two DHCPD servers using NTP to sync to the same time source? Are the 
time zones identical?

It looks like your failover setup is failing because there is too great a 
system time differential between the two servers.

-- 
        "History doesn't repeat itself; at best it rhymes."
                        - Mark Twain

| John Lucas                          MrJohnLucas at gmail.com               |
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