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thatguy
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PostPosted: Wed Aug 06, 2003 2:14 am    Post subject: skip eth0,etc. during boot if away from lan/wireless Reply with quote

I had the frequent annoyance of what seemed like an eternal boot when starting up my laptop in an office with no network or wireless. dhcpd would take what seemed forever to time out on each device. Here's a fragment to add to your /etc/init.d/net.ethx that will prompt you to skip or forge ahead with starting up your nic. default is to skip.
Code:

bypass() {
          ebegin "Press s to skip eth init"
              if read -n1 -t 2 choice
                  then
                      [[ "$choice" == "s" ]] && return 1 || return 0
                      else return 1
                  fi
      }
     
      start() {
          checkconfig || return 1
           bypass || return 1
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Garbz
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PostPosted: Wed Aug 06, 2003 3:13 pm    Post subject: Reply with quote

This is nice. This is much better than my original thought on this topic.

I wrote a script to change the runlevel based on my grub menu selection and skip net.eth0 / customize the bootup, but if i had known about this it would have been awesom.

Would also have cut the programming time from 15 min to about 5 :)

I may impliment this on my sister's laptop so she doesn't screw things up when picking runlevels ! Thanks.
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carambola5
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PostPosted: Wed Aug 06, 2003 7:43 pm    Post subject: Reply with quote

nicely done.

consider your code officially added to my laptop. works beautifully. I advise anyone with a laptop to implement this tip. I have always had to log in as root (or, I suppose issue a sudo command) in order to start up my wired/wireless cards.

It's simple tips like this that make life a bit easier for the average linux user.
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zojas
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PostPosted: Thu Aug 07, 2003 6:06 am    Post subject: Reply with quote

my laptop has two different ethernets (eth0 & eth1, eth0 is wired ethernet, eth1 is wireless). My solution was to create multiple virtual runlevels. 'default' starts up no ethernet, 'work' starts up eth0, 'home' starts up eth1. then at boot I have no network, once I log in I switch to the appropriate runlevel.

then I have different generic runlevels for wired ethernet with dhcp & wireless with dhcp. since the different runlevels need different settings in /etc/conf.d/net, I wrote some simple scripts which put different settings in conf.d/net then change the runlevel.

I have full details at the link in my sig. It's all slightly more complicated then just optionally skipping eth0 at boot, but it's MUCH more flexible.
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Garbz
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PostPosted: Thu Aug 07, 2003 7:17 am    Post subject: Reply with quote

It seems that everyone with a laptop found their own solution to the problem.

Is there anyway to background the process as well? I.e. let it start normally but don't halt the boot process for it ?

I am aware this would cause message to appear out of order.
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boobytrapped
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PostPosted: Sat Aug 09, 2003 4:07 pm    Post subject: ifplugd Reply with quote

You might want to check-out ifplugd http://www.gentoo.org/dyn/pkgs/sys-apps/ifplugd.xml.

Its a great daemon - it polls the eth port to see if media is present, and if so, would bring up the interface; like windows. Problem solved -- great for laptops.

I think its a bit hacky for the user to press a key if the eth cable is not plugged in so that dhcpcd does not keep on scanning like a idiot for an IP to become available.
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azote
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PostPosted: Wed Aug 13, 2003 7:13 pm    Post subject: Re: ifplugd Reply with quote

boobytrapped wrote:
You might want to check-out ifplugd http://www.gentoo.org/dyn/pkgs/sys-apps/ifplugd.xml.

Its a great daemon - it polls the eth port to see if media is present, and if so, would bring up the interface; like windows. Problem solved -- great for laptops.

I think its a bit hacky for the user to press a key if the eth cable is not plugged in so that dhcpcd does not keep on scanning like a idiot for an IP to become available.

great tool I love it !!

and today a new version came out (ifplugd 0.16 )
with Better WLAN association detection, a monitor mode for checking the availability of network interfaces (for PCMCIA)
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tank
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PostPosted: Wed Aug 13, 2003 9:06 pm    Post subject: Reply with quote

I installed ifplugd using the ebuild in portage.

However it does not seem to run dhcpd when it brings up an eth0
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Kasjopayer
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PostPosted: Thu Aug 14, 2003 12:37 pm    Post subject: Reply with quote

There's a workaround described in another thread, I will summarize it:
1. emerge ifplugd
2. emerge net-tools (if it isn't already emerged)
3. edit the net.ethX scripts as following:
https://bugs.gentoo.org/attachment.cgi?id=15471&action=view
(remove two lines, add one lines).
4. add in the config file /etc/conf.d/ifplugd the options "-a -mm" to ARGS:
Code:
ARGS="-f -u0 -d5 -w -a -mm"

5. rc-update add ifplugd default

net-tools is needed, because it inclues mii. It scans wheter a cable is plugged in (while the interface isn't up - that's the reason for using it - therefore -mm). The second option -a goes in the same direction, it doesn't enable the interface automatically. Otherwise ifplugd won't work with the net.ethX scripts.
Maybe there's a better way to solve it, but it works finally.
BTW: the option "-d5" defines the delay from plugging out up to shutting down the interface. Default is 20 seconds, I set it down to 5 seconds.

I hope this helps!

Kasjopayer
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snis
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PostPosted: Thu Aug 14, 2003 12:55 pm    Post subject: Reply with quote

...and another solution:

I read about this in a tread somewhere on the forum some time ago.
It requires sys-apps/mii-diag
And that you add the following lines to your net.ethX file:
Code:
else
                if [ ! -n "$(which mii-tool 2> /dev/null)" -o -n "$(mii-tool ${IFACE} | grep "link ok")" ]
#               if [ ! -n "$(which mii-diag 2> /dev/null)" -o -n "$(mii-diag --status ${IFACE} | grep "link bea
t" | grep "OK")" ]
                then
                        /sbin/dhcpcd ${dhcp_args} ${IFACE} >/dev/null || {
                                retval=$?
                                eend ${retval} "dhcpcd failed to bring up ${IFACE}"
                                return ${retval}
                        }
                else
                        eend 2 "No ethernet link on ${IFACE} detected - Network Not Initialized"
                        return 2
                fi
        fi


this is how my 'start' section looks like in /etc/init.d/net.eth0
Code:
start() {
        local retval=0

        setup_env
        checkconfig || return 1

        ebegin "Bringing ${IFACE} up"
        if [ "${iface_IFACE}" != "dhcp" ]
        then
                /sbin/ifconfig ${IFACE} ${iface_IFACE} >/dev/null || {
                        retval=$?
                        eend ${retval} "Failed to bring ${IFACE} up"
                        return ${retval}
                }
                # ifconfig do not always return failure ..
                /sbin/ifconfig ${IFACE} &> /dev/null || {
                        retval=$?
                        eend ${retval} "Failed to bring ${IFACE} up"
                        return ${retval}
                }

        else
                if [ ! -n "$(which mii-tool 2> /dev/null)" -o -n "$(mii-tool ${IFACE} | grep "link ok")" ]
#               if [ ! -n "$(which mii-diag 2> /dev/null)" -o -n "$(mii-diag --status ${IFACE} | grep "link bea
t" | grep "OK")" ]
                then
                        /sbin/dhcpcd ${dhcp_args} ${IFACE} >/dev/null || {
                                retval=$?
                                eend ${retval} "dhcpcd failed to bring up ${IFACE}"
                                return ${retval}
                        }
                else
                        eend 2 "No ethernet link on ${IFACE} detected - Network Not Initialized"
                        return 2
                fi
        fi

        if [ -n "${alias_IFACE}" ]
        then
                local x=""
                local num=0
                local aliasbcast=""
                local aliasnmask=""

                ebegin "  Adding aliases"
                for x in ${alias_IFACE}
                do
                        aliasbcast="$(eval echo \$\{broadcast_${IFACE}\} \| awk \'\{ print \$$((num + 1)) \}\')
"
                        if [ -n "${aliasbcast}" ]
                        then
                                aliasbcast="broadcast ${aliasbcast}"
                        fi

                        aliasnmask="$(eval echo \$\{netmask_${IFACE}\} \| awk \'\{ print \$$((num + 1)) \}\')"
                        if [ -n "${aliasnmask}" ]
                        then
                                aliasnmask="netmask ${aliasnmask}"
                        fi

                        ebegin "    ${IFACE}:${num}"
                        /sbin/ifconfig ${IFACE}:${num} ${x} \
                                ${aliasbcast} ${aliasnmask} >/dev/null
                        num=$((num + 1))
                        eend 0
                done
                save_options "alias" "${alias_IFACE}"
        fi

        if [ -n "${inet6_IFACE}" ]
        then
                local x=""
                ebegin "  Adding inet6 addresses"
                for x in ${inet6_IFACE}
                do
                        ebegin "    ${IFACE} inet6 add ${x}"
                        /sbin/ifconfig ${IFACE} inet6 add ${x} >/dev/null
                        eend 0
                done
                save_options "inet6" "${inet6_IFACE}"
        fi

        if [ -n "${gateway}" ] && [ "${gateway%/*}" = "${IFACE}" ]
        then
                ebegin "  Setting default gateway"
                # First delete any existing routes if it was setup by kernel ..
                /sbin/route del default dev ${gateway%/*} &>/dev/null
                /sbin/route add default gw ${gateway#*/} dev ${gateway%/*} \
                        netmask 0.0.0.0 metric 1 >/dev/null || {

                        local error=$?
                        ifconfig ${IFACE} down &>/dev/null
                        eend ${error} "Failed to bring ${IFACE} up"
                        stop
                        return ${error}
                }
                eend 0
        fi

        # Enabling rp_filter causes wacky packets to be auto-dropped by
        # the kernel
        if [ -e /proc/sys/net/ipv4/conf/${IFACE}/rp_filter ]
        then
                echo 1 > /proc/sys/net/ipv4/conf/${IFACE}/rp_filter
        fi
}


It works for me, I'm only using it on eth0 since I unplugg my wireless card if I'm not using it.
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Sven Vermeulen
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PostPosted: Thu Aug 14, 2003 1:25 pm    Post subject: Reply with quote

I just set the time-out value for dhcp to 5 seconds. If the DHCP server doesn't reply in 5 seconds, I know (1) something is wrong, or (2) there is no DHCP to request to (i.e. no medium connection).

Edit /etc/conf.d/net and set the dhcpcd_args so it contains "-t 5".
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Garbz
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PostPosted: Fri Aug 15, 2003 7:50 am    Post subject: Reply with quote

I've had an overly congested network at times, dhcp took way longer than 5 seconds to aquire :? I know it shouldn't
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StinkyLou
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PostPosted: Fri Aug 15, 2003 8:48 pm    Post subject: Reply with quote

Kasjopayer,

I followed your instructions, but I'm still having trouble.

Despite the fact that ifplugd loads on boot (before eth0 starts), eth0 still pauses for several minutes. I think I did everthing as you suggested, but I might have made a mistake. I have one concern in particular: when editing net.eth0, the two lines I removed and the line I added were from the stop() section of the file. Was that correct? I'd be happy to post my net.eth0 if you think that would be helpful.

I appreciate any input you can offer.

StinkyLou
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Garbz
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PostPosted: Sun Aug 17, 2003 1:22 am    Post subject: Reply with quote

yes the net.eth0 modification is correct.

Since ifplugd loads at boot and automatically handles the eth connection you should:

rc-update del net.eth0 default

since ifplugd will start it anyway when a cable is present.
The only problem with this method is that if a program which is dependant on on net.eth0 (and can't run without it i.e. mounting a remote filesystem) will start anyway and fail at boot.

As far as i've messed with it anyway.
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StinkyLou
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PostPosted: Sun Aug 17, 2003 5:08 am    Post subject: Reply with quote

Garbz,
Quote:
Since ifplugd loads at boot and automatically handles the eth connection you should:

rc-update del net.eth0 default

That did it--thanks!!! I never would have come up with that on my own.

Keep on keepin' on. :lol:

StinkyLou
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Garbz
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PostPosted: Mon Aug 18, 2003 12:29 am    Post subject: Reply with quote

lol ur welcome.
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BlackBart
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PostPosted: Mon Aug 18, 2003 1:42 am    Post subject: Reply with quote

I solved this by grepping he cardmanager stab file to see if my network card was installed. This won't work if you have a built in ethernet though.
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