ppp client not relinquishing IP address

[Ernie Luzar]

andrew clarke wrote:
> Hi,
> 
> I run my ADSL modem in bridge mode. Often when my the ADSL service
> disconnects for whatever reason, FreeBSD's ppp client will 'hold' the
> old IP address despite it no longer being connected:
> 
> $ ifconfig tun0
> tun0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> metric 0 mtu 1492
>         options=80000<LINKSTATE>
>         inet 203.206.32.1 --> 150.101.32.78 netmask 0xffffff00 
>         inet 114.198.37.186 --> 150.101.32.44 netmask 0xffffff00 
>         nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
>         Opened by PID 10470
> 
> What's causing this, and is there any way I can prevent it?
> 
> For one, ddclient doesn't update my dynamic DNS server with the new IP
> address.
> 
> My /etc/ppp.conf is as follows, and hopefully some useful bits of
> /var/log/ppp.log below it.
> 
> Thanks.
> 
> Regards
> Andrew
> 
> default:
>   set log phase ipcp ccp tun command
>   nat enable yes
>   enable echo
>   enable lqr
>   set speed sync
>   set ctsrts off
>   set ifaddr 10.2.0.1/0 10.2.0.2/0 255.255.255.0 0.0.0.0
> 
> iinet:
>   set device PPPoE:bge0
>   set authname username
>   set authkey password
>   set dial
>   set login
>   set mru 1492
>   set mtu 1492
>   set timeout 0
>   set redial 30 0
>   add default HISADDR
> 


Here are the commands you seek.

# Get dynamic IP address from ISP.
  set ifaddr 0.0.0.0/0  0.0.0.0/0  0.0.0.0  0.0.0.0

  enable dns             # Gets the ISP's DNS IP address & places them
                         # in resolv.conf for reference by FBSD.

  disable iface-alias    # Stop adding old IP address as alias when ppp
                         # redials because line was lost.

  iface clear            # Remove all previous IP address

  set redial 10 4        # if busy redial 4 times with 10 second pause




You should be using a firewall for NAT instead of doing it in ppp.