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Old 01-23-2011, 07:16 PM   #16
lpallard
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Guys, thanks for the feedback!

Today , this happened on my laptop:

1. Failed to get an IP from pfSense DHCP server
2. Tried to get an IP as root with /etc/rc.d/rc.inet1 eth0 restart => it failed but no error messages!
3. Tried again to get an IP as root with /etc/rc.d/rc.inet1 restart (note the missing eth0 argument) and it worked.

THats the complete opposite as what I reported before...

Now to your suggestion devwatchdog, I am a complete noob in networking so I would like to know how to use the tcpdump command....

Thanks!
 
Old 01-24-2011, 03:08 AM   #17
markush
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Hello lpallard,

open two terminals, in one of them use
Code:
tcpdump -i eth0
(note that there is only output if there's networktraffic, and in the other terminal use the commands you've mentioned in your post above (trying to get a lease via DHCP).

I think it would be better, to split the commands in two parts. If the interface, eth0 is up, you may use the command
Code:
dhcpcd eth0
in order to get a lease from the DHCP-server.

I'd also suggest to look at the output of "ifconfig" before and after executing the commands.

I would further suggest to read a tutorial about tcpdump http://tutorials.papamike.ca/pub/tcpdump.html it has alsoo a quite comprehensive manpage. You may also google for tcpdump, there's a lot of interesting information in the internet.

Markus

Last edited by markush; 01-24-2011 at 03:19 AM.
 
Old 01-24-2011, 08:42 PM   #18
lpallard
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OK I might not have progressed that much but considering my very limited networking skills, here's what I did:

I issued the dhcp renewal commands in a terminal and monitored the output of tcpdump in a different terminal.

Code:
root@xpsm1730:/home/lpallard# /etc/rc.d/rc.inet1 restart
Polling for DHCP server on interface eth0:
dhcpcd: version 5.2.2 starting
dhcpcd: eth0: waiting for carrier
dhcpcd: timed out
dhcpcd: allowing 8 seconds for IPv4LL timeout
dhcpcd: timed out
resulted in

Code:
root@xpsm1730:/home/lpallard# tcpdump -i eth0
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
20:36:47.535170 IP6 :: > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
20:36:47.884176 IP6 :: > ff02::1:ff48:97c8: ICMP6, neighbor solicitation, who has fe80::21d:9ff:fe48:97c8, length 24
20:36:48.887181 IP6 fe80::21d:9ff:fe48:97c8 > ff02::2: ICMP6, router solicitation, length 16
20:36:52.755174 IP6 fe80::21d:9ff:fe48:97c8 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
20:36:52.899178 IP6 fe80::21d:9ff:fe48:97c8 > ff02::2: ICMP6, router solicitation, length 16
20:36:56.907173 IP6 fe80::21d:9ff:fe48:97c8 > ff02::2: ICMP6, router solicitation, length 16
^C
6 packets captured
6 packets received by filter
0 packets dropped by kernel
and

Code:
root@xpsm1730:/home/lpallard# /etc/rc.d/rc.inet1 eth0 restart
Polling for DHCP server on interface eth0:
dhcpcd: version 5.2.2 starting
dhcpcd: eth0: broadcasting for a lease
dhcpcd: eth0: offered 192.168.0.106 from 192.168.0.100
dhcpcd: eth0: acknowledged 192.168.0.106 from 192.168.0.100
dhcpcd: eth0: checking for 192.168.0.106
dhcpcd: eth0: leased 192.168.0.106 for 28800 seconds
dhcpcd: forking to background
resulted in

Code:
root@xpsm1730:/home/lpallard# tcpdump -i eth0
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
20:37:48.360226 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 00:1d:09:48:97:c8 (oui Unknown), length 324
20:37:48.360808 IP 192.168.0.100.bootps > 192.168.0.106.bootpc: BOOTP/DHCP, Reply, length 300
20:37:48.360925 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from 00:1d:09:48:97:c8 (oui Unknown), length 336
20:37:48.361240 IP 192.168.0.100.bootps > 192.168.0.106.bootpc: BOOTP/DHCP, Reply, length 300
20:37:48.373233 ARP, Request who-has 192.168.0.106 tell 0.0.0.0, length 28
20:37:49.965947 ARP, Request who-has 192.168.0.106 tell 0.0.0.0, length 28
20:37:51.499654 ARP, Request who-has 192.168.0.106 tell 0.0.0.0, length 28
20:37:53.539188 ARP, Request who-has 192.168.0.106 tell 192.168.0.106, length 28
20:37:55.541183 ARP, Request who-has 192.168.0.106 tell 192.168.0.106, length 28
^C
9 packets captured
9 packets received by filter
0 packets dropped by kernel
which worked (got 192.168.0.106 from pfsense)

Hope this helps. Let me know what more I can do

Last edited by lpallard; 01-24-2011 at 08:43 PM.
 
Old 01-25-2011, 03:28 AM   #19
markush
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Hello lpallard,

this looks odd to me. On first sight it looks as if within the first trial to aquire a lease there are ipv6 packages.
The message "waiting for a carrier" means that there is no connection.

Do you have the ipv6-protocol enabled on your DHCP-server?

Since you're running Slackware, I'd suggest to post this issue (with the code of your above post) in the Slackware-forum http://www.linuxquestions.org/questions/slackware-14/

Hope that helps

Markus
 
Old 01-25-2011, 11:50 AM   #20
lpallard
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Odd.... I never played around ipv6 functions... AFAIK, my pfsense machine is not supposed to handle ipv6 packets at all. Like I said, if the pfsense machine was THE problem, I would see this behavior on evvery machine handshaking with it on my network. Also my htpc machine has the very same kernel (2.6.37) installed & compiled from scratch and does not behave like this..

So far what this is telling me:

the pfsense is probably not the root cause
the kernel 2.6.37 is probably not the root cause

I am thinking its either machine specific or some incompatibility/glitch between slackware 13.1 (32bit) and the new kernels.

I will post on the slackware forum to make sure if its a bug it gets tracked and solved properly.

Any other ideas or comments, please share.

thanks!
 
Old 02-01-2011, 11:20 PM   #21
lpallard
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Upgrading dhcpcd from stock 5.2.2 to -current's version 5.2.9 seems to have fixed the problem!

output of /var/log/messages at boot time:
Quote:
Feb 1 23:17:02 xpsm1730 logger: /etc/rc.d/rc.inet1: /sbin/ifconfig lo 127.0.0.1
Feb 1 23:17:02 xpsm1730 logger: /etc/rc.d/rc.inet1: /sbin/route add -net 127.0.0.0 netmask 255.0.0.0 lo
Feb 1 23:17:03 xpsm1730 logger: /etc/rc.d/rc.inet1: /sbin/dhcpcd -t 10 eth0
Feb 1 23:17:03 xpsm1730 dhcpcd[1954]: version 5.2.9 starting
Feb 1 23:17:05 xpsm1730 dhcpcd[1954]: eth0: waiting for carrier
Feb 1 23:17:07 xpsm1730 kernel: tg3 0000:09:00.0: eth0: Link is up at 1000 Mbps, full duplex
Feb 1 23:17:07 xpsm1730 kernel: tg3 0000:09:00.0: eth0: Flow control is on for TX and on for RX
Feb 1 23:17:07 xpsm1730 dhcpcd[1954]: eth0: carrier acquired
Feb 1 23:17:07 xpsm1730 dhcpcd[1954]: eth0: broadcasting for a lease
Feb 1 23:17:11 xpsm1730 dhcpcd[1954]: eth0: offered 192.168.0.106 from 192.168.0.100
Feb 1 23:17:11 xpsm1730 dhcpcd[1954]: eth0: acknowledged 192.168.0.106 from 192.168.0.100
Feb 1 23:17:11 xpsm1730 dhcpcd[1954]: eth0: checking for 192.168.0.106
Feb 1 23:17:16 xpsm1730 dhcpcd[1954]: eth0: leased 192.168.0.106 for 28800 seconds
Feb 1 23:17:16 xpsm1730 dhcpcd[1954]: forked to background, child pid 1997
Thanks to all !!
 
  


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