For laptop users: different network configurations

xkl · n00b Joined: 27 Sep 2003 Posts: 3

I think this is one of the main problems for laptop users. With this hack you will be able to switch between as many network configurations as you want. E.g. your home network, your work network, your university network and all networks of all your friends.

You are only three changes away from this. The first thing is a change deep in the startup files of the system.

Get the file /sbin/runscript.sh, change the line

hulk2nd · Posted: Mon Sep 29, 2003 7:08 pm Post subject:

weee!

looks really great, gonna test it immediately. but one question:

xianx · Posted: Tue Sep 30, 2003 5:00 pm Post subject: Exactly what i'm looking for!!

Yes Yes Yes! I just got my Wireless working last night (It was a long shot, ended up using acx100 and the Windows drivers that came on the CD

[USR2210 PCMCIA if anyone is interested])

And i'd like to know how to use multiple networks. I havent tried this yet, (i'm still at work) but i have a few questions already:

What do you do with resolv.conf? Obviously each network will have different DNS.

I actually will use eth0 for work, and wlan0 for home/coffee shops/etc. How does this change things?

thanks!

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al · Guru Joined: 26 Dec 2002 Posts: 304 Location: Scotland

Looks good.I'll have to try that sometime!

Posted using links.

nacul · n00b Joined: 12 Feb 2003 Posts: 9 Location: Irvine, CA

Hi,

I solved the same problem in a different way:

xkl · n00b Joined: 27 Sep 2003 Posts: 3

xkl · n00b Joined: 27 Sep 2003 Posts: 3

optilude · Posted: Wed Oct 15, 2003 10:57 pm Post subject: Alternatively...

For a slightly more generic solution, you could try my hprofile set of scripts:

https://forums.gentoo.org/viewtopic.php?t=46180

This integrates with the Gentoo runlevel model to let you arbitrarily replace configuration files and change runlevels based on an arbitrary condition. Simply put, this means you can use hprofile to automatically select the appropriate version of your configuration files (and individual users can change configuration files in their home directories), and your runlevel at boot, depending on your hardware configuration.

I use this so I can boot gentoo both within vmware and on its own, changing runlevels and files such as modules.autoload and XF86Config to files appropriate for the hardware configuration.

One important advantage over the original post here, besides being general purpose, is that it requires no manual editing of any gentoo rc scripts, which means that your changes won't be overwritten when you update baselayout etc. :-)

Best wishes,
Martin
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xentric · Guru Joined: 16 Mar 2003 Posts: 410 Location: Netherlands

After following xkl's little howto I just want to add a couple of changes that I needed
to make in order to get this to work...

1. Remove pcmcia from all runlevels:

tomapd · n00b Joined: 26 Aug 2003 Posts: 22 Location: Sendai

Thanks for a nice tip!!!
It's much better than my way.

xmoy · Posted: Wed Sep 22, 2004 6:28 pm Post subject:

I added this to my net.eth0 (after start() { )

Massimo B. · Posted: Sun Jun 26, 2005 4:15 pm Post subject:

Right now this is the part of my /sbin/runscipt.sh with the modified line:

UberLord · Posted: Wed Jun 29, 2005 11:08 am Post subject:

OK - this is vastly out of date. Here's what works with >=baselayout-1.11.12

if /etc/conf.d/${configfile}.${runlevel} exists then use that
else
if /etc/conf.d/${configfile} exists then use that

${configfile} is any file in /etc/conf.d which corresponds to a matching /etc/init.d/${script}
(exception - all net.xxx scripts load conf.d/net)
${runlevel} is the current runlevel

So in the runlevel foobar
/etc/init.d/vsftpd
load /etc/conf.d/vsftpd.foobar if it exists, otherwise /etc/conf.d/vsftpd

/etc/init.d/vsftpd.virtual -> /etc/init.d/vsftpd (symbolic link)
load /etc/conf.d/vsftpd.virtual.foobar if it exists, otherwise /etc/conf.d/vsftpd.virtual

/etc/init.d/net.eth0 -> /etc/init.d/net.lo (symbolic link)
load /etc/conf.d/net.foobar if it exists, otherwise /etc/conf.d/net

To change runlevel at boot, append "softlevel=foobar" to your kernel line. This would change you to the foobar runlevel.
You can use "rc foobar" to do the same thing at the command prompt.

househead · Posted: Thu Jul 14, 2005 1:04 pm Post subject:

jamapii · l33t Joined: 16 Sep 2004 Posts: 637

I prefer (and use) a much simpler solution. I don't change any baselayout files, I don't make a lot of copies of config files, I don't create additional links in /etc/init.d/... and (optionally) I try to trim down the number of runlevels.

My first approach is to create runlevels if necessary. The "softlevel" variable contains the runlevel name. Now I take advantage of the fact that (almost all) /etc/conf.d/... files are just shell scripts sourced in, so I make the variables depend on $softlevel.

This may be doomed if the config files aren't really meant to be shell scripts, but I still prefer it over maintaining a baselayout patch, initscript links and multiple copies of nearly identical conf.d files. With my solution, the complex and ugly stuff is contained in a few config files.

Depending on the location, I put preup() / postup() functions in the environment that fix the config files for dependent services, e.g. sendmail and ntpd.

My favourite ultimate solution would be to detect the location automatically at boot, possibly by switching on all network cards and trying to find out what MAC addresses are on the net, using $softlevel as a hint. That's what I did on the old laptop. Using dhcp as much as possible is also a good thing for laptops.

The order in which config files are sourced is important, up to recently it was just simply backwards - generic overrides specific. But the changes mentioned by UberLord seem to make it much more complex, so it should be used with caution.

I won't use separate config files for runlevels if it prevents the generic file from being sourced, because it probably involves a lot of duplication. But if the config files someday aren't treated as scripts anymore, I'll have to find a new solution.

househead · Posted: Thu Jul 14, 2005 2:24 pm Post subject:

I actually think the baselayout method is far simpler. I just need to figure out a method (without using dhcp) that I can use different DNS servers depending whether I am on the wired work network, or my wirleless home (vpn'd) network
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jamapii · l33t Joined: 16 Sep 2004 Posts: 637

Massimo B. · Posted: Sun Jul 31, 2005 11:43 am Post subject:

So finally I have to correct my (still working) net configs to the new baselayout.
That's the interesting point:

Massimo B. · Posted: Sun Jul 31, 2005 1:36 pm Post subject:

It doesn't work the way you've told:

dirtyd · n00b Joined: 11 Apr 2005 Posts: 3

Check this out:

http://www.gentoo.org/doc/en/handbook/2005.1/handbook-x86.xml?full=1#book_part4

specifically: