Hi. A while ago, I downloaded Ubuntu 5.04. Very, very happy! Stable, all my hardware supported, simple to use. Anyway I've been using it about two months now, and suddenly it will not boot anymore. On boot, it just freezes at the line "Starting Hotplug Subsystem...". Now, around the forums I've seen plenty of posts saying that they've just installed linux and this problem happens - but I've already been running Ubuntu for two months with no problems, I have changed no hardware or anything. I am at a complete loss - and stressed as I have a project due in a week that I need to compile under linux!

I have (after backing up my stuff) reformatted and reinstalled Ubuntu yet same problem. After googling my ass off I have found some people saying that when hotplug hangs on boot like this a module has died, and therefore linux will not load the next module and continue booting. He vaguely described a process where I press Alt-SysReq-e to kill all the processes at runlevel 2, and then it should continue booting or something. Nothing happens when I press these keys. In fact, typing anything does not show up on the screen like normal when booting (and no, I'm not using a usb keyboard). Somebody else said that to see the module which has died, I should type in dmesg to see logs of the boot, then put the broken module in /etc/hotplug/blacklist.d. However, how am I supposed to type dmesg and blacklist modules if my computer will not boot? Anybody have any ideas? Please....?

Maybe try booting without hotplug. At the boot loader provide the kernel with a boot parameter like this.

kernel kernel_image nohotplug

I tried that but no cigar. The starting hotplug message still appeared and still hung there. Did I do this wrong? I'm using grub bootloader if this helps. I appended nohotplug on the end of the line which said 'kernel /boot/vmlinuz-2.6.10-5-386 root=/dev/hdc1 ro quiet splash', then pressed 'b' for boot. The nohotplug message appeared appended to this line as I edited it, however it didn't seem to take any effect. Anybody got any ideas?

Try booting into single mode. In there, try to disable the hotplug service. I don't know how to boot into single mode for ubuntu, but it should be somewhat similar to other distros. Append single or 1 to the kernel boot parameters. If this doesn't work, check the documentation. Once you get in, go to the /etc/rc.d or similar directory. Disable the rc.hotplug service by running chmod -x rc.hotplug

This might be somewhat different for Ubuntu (I was talking Slackware way to do it here)

You can also usually find an "interactive startup" in which you will be prompted, Y/N, whether you want to run a particular startup-script.

Once you do get the system up, look at /var/log/messages.

Yes there is a single user mode. It's present on the grub list of what to boot along with the normal boot method but unfortunately it still tried to load hotplug. As for the interactive startup thing, I think that comes into effect after hotplug is already loaded, as I haven't seen a question asking whether to enter interactive startup. I couldn't get around this with some kind of live-cd or something?

Hey there...

I've had (sorta) the same problem. I'm a new linux user, had an old dell pc laying around and figured I should learn my way around it.

Anyway, when I installed linux, everything was fine until it booted up. It gave the "Starting hotplug subsystem..." hanging error. Being new to linux, I had no idea what to do. Eventually, I got around to disabling my pci graphics card and enabling the onboard video, which got it to boot up correctly.

I know you were running this for a couple months before this, but I thought I would toss this out to you in case it helped. Maybe it has something to do with a pci slot or graphics card drivers.

I also have the same problem with it freezing - well, when I type Control+C it shows up as ^C - on starting hotplug subsystem. (I am on Ubuntu 5.10). But then I manually turn the computer off, and when I restart it, it goes through checking the hard drive, and at the end, it doesn't hang there, though it doesn't display OK either.

This only happens after I have just run Windows - all the other times it doesn't freeze.