Arch Linux

PiousMinion

Member

Registered: 2009-07-21

Posts: 12

xen domU archlinux - no login prompt

I have tried for some time to get a working archlinux guest (domU) on xen with no success.

The kernel loads just fine, the root fs is mounted, and the services are started.  After that, nothing. The screen stops at showing the last service that was started. I get no login prompts and I've been told it has something to do with not having tty(s).

I've asked multiple times in IRC and keep being told that this very problem has been discussed in the forums(here) and in the mailing lists.  Yet, I have searched very thoroughly and haven't been able to find anything on this.

I'm sure "someone" out there has a working xen setup.
Can someone please provide info on this?

thanks

Last edited by PiousMinion (2009-10-31 08:56:44)

Lastebil

Member

From: Suomi

Registered: 2007-01-16

Posts: 35

Re: xen domU archlinux - no login prompt

Whoops, sorry, I was ... away.

Answering this MAINLY for anyone searching for a similar issue.

The "problem" mentioned above looks to me like an issue with not setting up the console to allow login from the xen serial interface - which is what you're looking at if you're doing 'xm console blah.cfg'

So yes, everything is working just fine - services starting, but 'no login on the console.'

There are 2 solutions for this, the obvious, and the one that is possibly less work (:

1. Enable login on the console (:
  - The xen console is hvc0.  (HyperV Console 0, one could suppose.)
  - if you have an EARLY xen build for some reason - the console may be called 'xvc0' (Xen Virtual Console 0, I suppose.)

Read up on what /etc/securetty does, and edit appropriately.
  - I am saying this because you may not have to edit at all, depending on what your xen install did when it was installed.  UNDERSTANDING what the file does will save you from wondering 'do I need to do something?' or KNOWING that you do or don't.

Read up on what /etc/inittab does, what your getty does, and how to install a console session on some tty.
  - There's more than one way to do this, and you may want to use a different 'getty' program for dealing with the serial than the normal one that talks to your normal physical arch console.  There are many 'getty' programs, some work with serial terminals much better than others.  And you ARE using a serial terminal here, despite any arguments you have that it isn't - it is a virtual serial terminal, so treat it like a phsical serial terminal and understand what it's doing.
- You're basically saying "yes, allow a root login on serial instance 'hvc0' here."
- Something like: "c1:2345:respawn:/sbin/mgetty -8 1200 hvc0 vt100" will be in there.  (You SHOULD look at that line, compare to the line in your current /etc/inittab, and see what I changed, and understand what the options do so it WORKS FOR YOU.  I would seriously NOT run a 1200 baud connection, btw (:  )

Areas to read:
man agetty
man inittab
man securetty
man login

other gettys in pacman:  fgetty, fbgetty, and qingy.  Since the last 2 use framebuffers, you REALLY should consider whether they'll work for you on a VIRTUAL SERIAL CONSOLE before you use them (:  (Hey, they might. You might really love how they work.  Know what you are doing and what you want, and things _work._)

Also, though really difficult, the mailing lists for xen GENERALLY have the answer buried SOMEWHERE in there.  You just have to keep reading and understanding.  After a while, you actually get good at finding stuff in there.  The mail list archives are pretty good if you keep reading/discarding/learning.

Finally, I've been using Xen professionally now for, what, 4 years?  It's changed a lot, but it's done extremely well for me - though I have NOT used it as a dom0 until, well, just now - so we'll see how that goes.  The MAJORITY of the installs I have are Debian dom0 and a few Centos5.  I dislike the Centos version a lot.  We'll see how the Arch thing goes - as I look to expand to more 'cloud' type things.

Lastebil

Member

From: Suomi

Registered: 2007-01-16

Posts: 35

Re: xen domU archlinux - no login prompt

CRAP I didn't mention 'part 2: the "easier" solution.'

Remember how "all services are started?"

Yeah, well, you installed ssh, didn't you?

SSH over.  Problem solved (:

Ghost1227

Forum Fellow

From: Omaha, NE, USA

Registered: 2008-04-21

Posts: 1,422

Website

Re: xen domU archlinux - no login prompt

I can't even get an arch guest to boot on XEN

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