Linux Gateway PPOE

[Crash]

I configured a Mandrake 10 Linux box with shorewall on the two interface setup (this you probably know from my earlier posts).

This acts as a gateway for all the pc's in my house.
Now I was getting a lot of disconnections for some reason. Same time other people on this forum were complaining. I was blaming WBS for this.

One day I got really annoyed and pulled the I-Burst off the linux box. It would disconnect and wouldn't reconnect for anything, and according to WBS the tower wasn't down. It was using pppoe (on the ethernet cable obviously).
I connected it directly to my windows box with the USB cable. And the damn thing connected and worked fine.

I thought this might have been a fluke. But I've checked it plenty of times.
When pppoe linux won't connect, the usb pppoe miniport does.

Could there be a problem with the pppoe on the ethernet port of the I-Burst Modem?
Maybe it's just my modem?????

Now you may want to blame the linux box, but I've connected an ADSL to shorewall with the same configuration, no problems.

What do you guys think? Maybe next time you linux box disconnects, plug it into the USB on your windows box and try connect.

Although, people who use windows and can't connect will blow this out the water.
I'm not sure. It just seems strange to me.

 

[kuberkoos]

pppoe's working fine for me on linux. i _do_ sometimes get that it won't reconnect immediately after a disconnection. log messages says someting about "timeout wating for PADS packets"

this happens rarely, and then only when the overall connectivity is fluctuating or downright bad. i once had a 56 hour connection. (that i've seen, there could have been longer ones...)

i usually just kill pppd and restart by hand.

are you it's not MTU problems or iptables setup gremlins?

chz,
kk

 

[alchamy]

could be gremlins, I had a few problems with my router initially but after doing my tables from scratch everything seemed to be sorted.

Otherwise its far more stable than windows, when disconnected (which happens often enough) it reconnects instantly. I hardly notice it. Besides MSN going mad in the taskbar. Windows tends to struggle with the reconnect, invalid passwords and all kinds of odd errors.

 

[Crash]

Okay.... I did chang the MTU size to 1392. But yeah it could be Gremlins somewhere. I'll have a go sometime in the next hundred years or so....

 

[Mayh3m]

Hi Crash

I did experience the same thing. Connection was down for a long while using ipcop with pppoe. Plugged it into my windows box and it came up. I thought that I had maybe just dislodged the cable when I was tinkering at some time, because when I put it back into ipcop box it came up. Thought it was flook or something.
It only happened that one time and since then, connection has been disconnected so much.

 

[zepher]

The same type of problem has also been occurring with my IPCOP 1.4 using PPPOE.

It just seems to get into a knot and will not connect.

On some occasions it is resolved by rebooting IPCOP and/or resaving the dial-up properties.

I have not changed the MTU to 1392 yet. The PPPOE is currently connecting at 1400 and the red interface is at 1500. Not sure if that could be an issue.

After the reboot or config save the modem connects and the bandwidth is awesome.

I have noticed a degradation in bandwidth prior to the modem link dropping and IPCOP being unable to connect.

Have been to lazy/busy to really investigate what is happening. The irritation level has not made it a priority yet.

 

[Crash]

Well, If I run the I-Burst on Windows with the USB cable or the Ethernet cable I don't have any problems. With both ways I stayed connected for about a week with perfect speeds.

Once it goes to the Linux box I get the disconnects and no reconnections all the pppoe says it "timed out".
It could be that the I-burst PPPOE doesn't stick 100% to the RFC. So linux is expecting something, and isn't getting it. There must be a way too solve this?

 

[kuberkoos]

I have not changed the MTU to 1392 yet. The PPPOE is currently connecting at 1400 and the red interface is at 1500.

huh? ppp0 should be you "red" interface. not? (i dont use ipcop/smoothwall myself) your "inside" interface ("green" ?) sounds right at 1500, the default for ethernet.

my ppp scripts initialises my ppp0 interface with a MTU of just over 1400. i had to put "ifconfig ppp0 mtu 13xx" at the top of my firewall script, which runs just after ppp startup, to force the MTU to what is should be.

now, if you don't want to lower the MTU's on your protected PC's then you'll have to employ the "MSS-clamping" hack on your firewall machine - This hack just zaps the first packet of an outgoing request a little. It effectively tells the server not to send TCP segments bigger than a certain size.

This is needed because on SOME paths on the internet, the MTU discovery gets fuxxored by routers that are not set up to make it work.

chz,
kk

 

[necro1234]

Hey guys

I just got Wireless Internet setup here via AEROSAT.
Im using IPCOP 1.4.10 and all connected fine with PPPOE, during the day I noticed some disconnects for no apparent reason.
At about 9:30Pm they started to get really bad dropping sporadically every few minutes.
By 10Pm I could not connect anymore, the logs where moaning that there was no responce and a timeout to PADO packets.
Anyhow I read up on here about the MTU settings, I went into /etc/rc.d/rc.red and changed the MTU/MRU values from 1492 to 1352.
I restarted my system and I have noticed some DRASTIC CHANGES.
Firstly the IPCOP box connects in half the time than before, next I was experiencing a massive packet loss with apps like MSN Messenger.
A large amount of the messenges "could not be delivered" or vanished for no reason.
Now there has not been 1 dropped message and the connection has been up and running all night without 1 further disconnect or hitch.
My traffic graphs from NTOP also look far more consitant and stable.

Cheers n thanx

Sheldon

 

[i-Guru]

@Crash
have you tried to compile the iburst USB drivers for mandrake, I am using suse9.3, compiled the iburst USB drivers for it,
and have never ever had a problem

Try it, let us know what you find

 

[Ravilj]

i-Guru you do know that this thread is from feb 2005.

 

[i-Guru]

ooops, did not read the date

 

[Crash]

Ah, the good old days. When the network was unshaped and uncapped