Apparently my mtu setting for tun0 is 1500 (from netstat -rn) and it
should have been set to 1452. I do have in my ppp.conf file "set mtu
1452" but I clearly has not done that. So, how should I go about this?

Here is my /etc/ppp/ppp.conf

default:
set log Phase Chat LCP IPCP CCP tun command
set redial 15 0
set reconnect 15 10000

pppoe:
set device "!/usr/sbin/pppoe -v -n Shasta_1 -i dc0"
set mtu 1452
# set mru 1452
set speed sync
disable acfcomp protocomp
deny acfcomp
enable lqr
set lqrperiod 5
set cd 5
set dial
set login
set timeout 0
set authname sigma@bslv3.mts.net
set authkey n38xl9w
add! default HISADDR
enable dns
enable mssfixup

I realized my *very* stupid mistake. It's already changed. I will now
curse myself for the next while.

Yes, I've tried using:

ifconfig tun0 mtu 1452

But that change is registered in ifconfig -a and not in netstat -rn?!?!

Reid Nichol wrote:
> I realized my *very* stupid mistake. It's already changed. I will
> now
> curse myself for the next while.
Re-reading this rested, I realize that I should state that here I refer
to the password thing and not the problem that I'm asking help for.

On 09/07/2004 12:20 AM, Reid Nichol wrote:

> Apparently my mtu setting for tun0 is 1500 (from netstat -rn) and it
> should have been set to 1452. I do have in my ppp.conf file "set mtu
> 1452" but I clearly has not done that. So, how should I go about this?
>
man 8 ppp is appropriate here, I think:

"The default MTU is 1500. At negotiation time, ppp will accept
whatever MRU the peer requests (assuming it's not less than 296
bytes or greater than the assigned maximum). If the MTU is set,
ppp will not accept MRU values less than value. When negotiations
are complete, the MTU is used when writing to the interface, even
if the peer requested a higher value MRU. This can be useful for
limiting your packet size (giving better bandwidth sharing at the
expense of more header data).

"If the ``maximum'' keyword is used, ppp will refuse to negotiate
a higher value. The maximum MTU can be set to 2048 at most."

I've set the following in my ppp.conf:

set mtu max 1492

ifconfig tun0 shows an mtu of 1492

BTW, unless you have a specific reason to set the mtu to 1452, my
understanding is that pppoe requires this to be 1492.

-- cm