Eskimo North

I installed ubuntu linux some time ago, and was really happy with it. All my peripherals worked, including scanner, card reader, I was even able to hot-sync my Palm pilot. Support was really helpful, and the synaptic package manager was pure bliss.

however, all the ubuntu packages & support forums are on the canonical.com servers, and for the past few months canonical has dropped into some weird never-neverland & I cannot get any webpage served by them. They all time out while connecting, regardless of which browser I use. and other than canonical I'm not having this problem. I've emailed eskimo north support, who tried to help, and the webmaster at canonical, who never replied. Everybody I know has had no problems connecting, but they all have high-speed connections - so I'm wondering if the problem has something to do with timing & the slower response time of good ol' 56k.

So, if anybody else out there is still using dial-up, I'd appreciate it if you could point your browsers to these addresses:

https://answers.launchpad.net/ubuntu
http://www.ubuntu.com/

and report back regarding success or failure. At the very least I can confirm or deny that the problem is just me, and only with the canonical servers (did I piss somebody off??)

In the meantime, my OS is frozen in time, because I can't get upgrades, can't get support, can't even order a new cd. It's nuts

anyway, thanks for listening, and thanks in advance for any help/info.

Having looked into this a little bit, I believe it is an issue with MTU discovery which is turned on by default in Linux. MTU discovery works by sending a large packet to the destination with the "do not fragment" bit set. If the far end returns a destination unreachable ICMP packet, it then steps the MTU down and tries again, and does this repeatedly until it finds the MTU that can be passed without fragmentation.

The problem with this is that it requires that destination unreachable packets can make it back to the sender, but these are frequently filtered to prevent denial of service attacks and to reduce the information available to an outside prober trying to find something to exploit.

In the case of canonical's sites; they have ICMP blocked at the gateway router. This will break MTU discovery. I suggest turning MTU discovery off:

And manually setting the MTU to a low value such as 576:

I'm not familiar enough with Ubuntu or /etc/pppoptions to tell you what to place there but manually setting it after the connection is established with ifconfig should at least allow you to determine if that is in fact the issue.