Multiple NIC Hosts

[cspence]

Added full paths. Replaced the ifconfig with the iproute2 replacement (it’s best to move away from a legacy tool). Redirected output to /etc/network/interfaces. If we slap this into /etc/init.d/S40network before the case statement, that should be a fix. I’ll be able to test it on Monday.

[CODE]for iface in $(ls -1 /sys/class/net | tr -d ‘@’)
do

all interface need to be up or you will get an invalid

argument error when checking the link state

/sbin/ip link set $iface up
linkstate=$(/bin/cat /sys/class/net/$iface/carrier)
if [[ “x$linkstate” = “x1” ]]
then
if [[ “x$iface” = “xlo” ]]
then
echo “auto lo” > /etc/network/interfaces
echo “iface lo inet loopback” >> /etc/network/interfaces
else
echo “auto $iface” >> /etc/network/interfaces
echo “iface $iface inet dhcp” >> /etc/network/interfaces
echo -e “\tudhcpc_opts -t 100 -T 20\n” >> /etc/network/interfaces
fi
fi
done[/CODE]

[Tom Elliott]

I’m adding this change to the inits.

All you’d have to do is, if you’re running the latest SVN versions, re-run the installer.

[cspence]

Good to hear! Thanks everyone.

[Tom Elliott]

From what I’m seeing, we don’t need the -l on the ls.

Why? Because the link is back to the /sys/devices/<location> and the separation in that folder contains multiple delimiters we need to break from. Will correct, but the for loop, from what I can see only needs to be ls /sys/class/net | tr -d ‘@’

[cspence]

[quote=“Tom Elliott, post: 42949, member: 7271”]From what I’m seeing, we don’t need the -l on the ls.

Why? Because the link is back to the /sys/devices/<location> and the separation in that folder contains multiple delimiters we need to break from. Will correct, but the for loop, from what I can see only needs to be ls /sys/class/net | tr -d ‘@’[/quote]

Careful, that’s not an “L”, that’s a “One.” He set it up to do one file/directory per line.

[Tom Elliott]

ahhhhh so difficult to tell sometimes.

[Sebastian Roth]

[quote=“cspence, post: 42950, member: 28749”]Careful, that’s not an “L”, that’s a “One.” He set it up to do one file/directory per line.[/quote]
That’s right, thanks for clarifying. And thank you Tom for adding this straight into the project. I really hope that it’s not causing any trouble for other users…

[Tom Elliott]

It shouldn’t pose problems unless the nic is unsupported, in which case they’d already be having problems regardless of with or without these tweaks.

[Tom Elliott]

so apparently this isn’t working properly.

I’ve changed the for loop to only add if the interfaces found does not match lo and eth0. My testing side seems to work properly, but other’s are seeing really strange things, particularly that the nic’s aren’t getting IPs. I don’t know why, maybe I can get some help over here?

[Sebastian Roth]

Sure I am happy to assist as much as I can!! Looking at the script in current SVN I noticed that you create ‘/etc/network/interfaces’ new from scratch (by using ‘>’) when ‘lo’ is detected. Normally that would be a good idea but when running this in my FOG test environment (QEMU) I end up with this:
[CODE]auto lo
iface lo inet loopback[/CODE]

Why you ask?? Because ‘lo’ does not necessarily come first. Actually on most systems ls is sorted by alphabet and ‘e’ comes before ‘l’. Do you know what I mean?

Fix: Use “>> /etc/network/interfaces” everywhere instead of “> /etc/network/interfaces”. If you want to make sure that it’s empty then do “echo > /etc/network/interfaces” before the for loop.

[cspence]

By default, udhcpc uses eth0. You will probably need to add -a $iface to udhcpc_opts. I was unsure if that would be taken care of by /etc/network/interfaces.

[Tom Elliott]

What’s weird, though, is the /etc/network/interfaces appears to get the proper values set (without the -a) but even without eth0 should still be found with little issue, and without these tweaks (reverting back to only having iface eth0) everything functions properly.

[cspence]

[quote=“Tom Elliott, post: 43023, member: 7271”]What’s weird, though, is the /etc/network/interfaces appears to get the proper values set (without the -a) but even without eth0 should still be found with little issue, and without these tweaks (reverting back to only having iface eth0) everything functions properly.[/quote]

Actually, I was trying to go off memory. The flag is [B]-i $iface[/B]. You don’t want to use -a. Sorry about that.

[Tom Elliott]

Updated to reflect the change. Pushed to inits as well.

[Tom Elliott]

Would the problems we’re seeing be related to the fact we bring the interface up, but we don’t bring it back down, so when the interface is added and the loop happens, it can’t get dhcp because it believes the link is up?

[cspence]

Finally got a chance to play with it, and I have a solution.

Insert a 5-second sleep between setting the interface up and checking the link status (we can’t just check before it gets a chance to find out if it is connected to a cable). Here’s the snippet as modified.

[CODE]…
/sbin/ip link set $iface up

Provide time for the interface to update linkstate

sleep 5
linkstate=$(/bin/cat /sys/class/net/$iface/carrier)
…[/CODE]

Works on my end.

…and if you wait just a second, I’ll have an optimized version…

[cspence]

[CODE]# Enable all interfaces
ifaces=$(ls -1 /sys/class/net | tr -d ‘@’)
for iface in $ifaces; do
/sbin/ip link set $iface up
done

Provide time for interfaces to detect their state

sleep 5

echo “auto lo” > /etc/network/interfaces
echo “iface lo inet loopback” >> /etc/network/interfaces

for iface in $ifaces; do
linkstate=$(/bin/cat /sys/class/net/$iface/carrier)
if [[ “x$linkstate” = “x1” -a “x$iface” != “xlo” ]]; then
echo “auto $iface” >> /etc/network/interfaces
echo “iface $iface inet dhcp” >> /etc/network/interfaces
echo -e “\tudhcpc_opts -t 100 -T 20\n” >> /etc/network/interfaces
fi
/sbin/ip link set $iface down
done[/CODE]

This solution only requires one sleep rather than five-seconds of sleep time per interface.

Edit: Fixed typos.

[Tom Elliott]

Bad statement.

linkstate=$(/bin/cat /sys/class/net/$iface

Should be
linkstate=$(/bin/cat /sys/class/net/$iface)

[Tom Elliott]

Also, shouldn’t the tr -d be tr -d ‘@’ not tr -d ‘0’?

[cspence]

[quote=“Tom Elliott, post: 43117, member: 7271”]Also, shouldn’t the tr -d be tr -d ‘@’ not tr -d ‘0’?[/quote]

Sorry, I was copying off code from my cellphone and wasn’t thinking about what I was typing. Also caught another typo on the udhcpc_opt statement.

Fixed the typos in the original post.