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Thread ID: 49281 2004-09-14 23:13:00 MDK Lin N/Hhood Dianne2 (6160) Press F1
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272433 2004-09-15 23:05:00 I thought that'd happen.

That's okay, Graham's been using Redhat a little too long ;-)

Try:
su -
[enter root pw]
/etc/init.d/network stop
/etc/init.d/network start

This should stop your network, and restart it - thereby forcing it to re-assign a Dynamic IP address. 		Chilling_Silence (9)
272434 2004-09-16 01:58:00 Right . :D

Here's the high technology way to do this .

Make a file in /root/bin called IP_Check (if you haven't got a /bin, make it -- mkdir /root/bin) . This file (saved as TEXT, not a WP file) contains:
#!/bin/sh
# have a look at the IP address we have and take some action
#
delay=5
if [ `ifconfig eth0` | grep 127 |wc -l != 0 ] ; then
echo -n " IP_Check: IP is local --- DHCP not working?";
service network restart; #NOTE 1
echo -n " IP_Check: Have restarted network, will check again in $delay minutes";
at now + $delay min -f /root/bin/IP_Check 2>/dev/nul;
else
echo -n " IP_Check: IP address looks OK";
fi


Then
find /etc -name rc . local will find that file for you . Edit that and put in the line
/root/bin/IP_Check

This was just a few minutes playing last night . . . it works for me . :D

At the line marked NOTE 1 use

ipdown etho
ipup eth0

or

ifconfig eth0 down
ifconfig eth0 up

or whatever works .

Samba might get clouted in this . . . as you have noticed . . . so you might have to include

service samba start

or

/etc/rc . d/init . d/smb start
/etc/rc . d/init . d/nmb start

as well .

Nice and simple, isn't it . :D 		Graham L (2)
272435 2004-09-16 02:50:00 Graham,

Thank you, I think it will take me a while to under stand that. I have coppied it, and shall studie it later.

Dianne 		Dianne2 (6160)
272436 2004-09-17 03:09:00 There's an oops in that . . . "left as an exercise for the reader" . I wish :D

The second "`" character in the test line is in the wrong place . That line should be:
if [ `ifconfig eth0 | grep 127 | wc -l` != 0 ] ; then The bolding also makes the pipe character "|" look very much like a lowercase "L" "l" . :-( The argument to the wc is "-l" the lowercase "L" .

What that line does is: ifconfig asks for the configuration of the eth0 interface, and passes it (through the pipe--"|") to grep which finds and passes any lines containing "127" to wc (the wordcount programme) with the -l (lines) option . The "`" characters surrounding that return the value of the expression -- which will be 0 or 1 . That value is used in the comparison The whole catastrophe contained in the "["and "]" brackets is a logical comparison (is the value NOTEQUAL ("!=") to 0 and returns TRUE or FALSE . The punctuation (including spaces) must be exactly right .

Try building the line up as a series of direct commands .

ifconfig eth0
then up-arrow,and add the pipe and grep,
ifconfig eth0 |grep 127
then up-arrow, and add another pipe and wc,
ifconfig eth0 | grep 127 | wc -l
then up-arrow, and change the 127 to a number you'll get and enter that


The reverse ticks "`" are used to explicitly pass the result to, e . g . , the if operator in script .

Doing it this way will make it "automatic " . . . and users won't have to know the root password . 		Graham L (2)
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