LinuxQuestions.org - Problems connecting after Power cut

- Linux - Newbie (https://www.linuxquestions.org/questions/linux-newbie-8/)

- - Problems connecting after Power cut (https://www.linuxquestions.org/questions/linux-newbie-8/problems-connecting-after-power-cut-704141/)

Problems connecting after Power cut

First post:

Hello everybody.

I recently installed Debian etch 4.0, (only successful after reading posts on this forum!) So I thought this would be the best place to seek assistance:

I have a server running Debian etch connected to a BT Adsl modem. On the MODEM I have port forwarding on 21, 80, 3306 and 10000. I have a remote machine that I used to connect over the internet to the server ie xxxx.dynalias.org. Evertyhing was working just fine, then a power cut shut everything down. So I rebooted and discovered that I was not able to connect from the remote machine on port 80 or 10000 but still able to connect on 3306..........ARGGGGGGHHH!!!!

ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:00:6C:41:4F:AA
inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::200:6cff:fe41:4faa/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:10357 errors:0 dropped:0 overruns:0 frame:0
TX packets:9856 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:8081252 (7.7 MiB) TX bytes:1627308 (1.5 MiB)
Interrupt:225 Base address:0x4000

/etc/network/interfaces

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
# allow-hotplug eth0
# iface eth0 inet dhcp

auto eth0
iface eth0 inet static
address 192.168.1.10
netmask 255.255.255.0
gateway 192.168.1.1

What else should I check? On the top right of my desktop I see an icon that states "No Network connection" Yet I am still able to connect to the internet!

Quote:

So I rebooted and discovered that I was not able to connect from the remote machine on port 80 or 10000 but still able to connect on 3306..........ARGGGGGGHHH!!!!

Are you sure that these ports are listening on your box? Because if it was your route, it would also block port 3306. What is the output of:

Code:

netstat -tan|grep -E '80|10000'

Many thanks for your help,

I issued the command: netstat -tan|grep -E '80|10000'

tcp 0 0 0.0.0.0:10000 0.0.0.0:* LISTEN
tcp 0 0 192.168.1.10:47990 69.88.148.130:80 ESTABLISHED
tcp 0 0 192.168.1.10:47994 69.88.148.130:80 ESTABLISHED
tcp 0 0 192.168.1.10:37037 75.126.162.205:80 ESTABLISHED
tcp 0 0 192.168.1.10:37038 75.126.162.205:80 ESTABLISHED
tcp 0 0 192.168.1.10:44892 74.201.118.102:80 TIME_WAIT
tcp 0 0 192.168.1.10:44902 74.201.118.102:80 TIME_WAIT
tcp 0 0 192.168.1.10:44899 74.201.118.102:80 TIME_WAIT
tcp 0 0 192.168.1.10:39953 213.123.85.200:80 ESTABLISHED
tcp 0 0 192.168.1.10:50329 212.140.233.223:80 ESTABLISHED
tcp 0 0 192.168.1.10:34922 74.201.118.102:80 TIME_WAIT
tcp 1 0 192.168.1.10:38467 66.102.9.166:80 CLOSE_WAIT
tcp 1 0 192.168.1.10:58260 66.102.9.155:80 CLOSE_WAIT
tcp 1 0 192.168.1.10:58258 66.102.9.155:80 CLOSE_WAIT
tcp 1 0 192.168.1.10:58265 66.102.9.155:80 CLOSE_WAIT
tcp 1 0 192.168.1.10:44418 216.239.59.127:80 CLOSE_WAIT
tcp6 0 0 :::80 :::* LISTEN

I'm not an expert, but it seems all is not well.

Any ideas?

TYIA

Quote:

tcp 0 0 0.0.0.0:10000 0.0.0.0:* LISTEN
tcp6 0 0 :::80 :::* LISTEN

Both ports are listening, so I guess it's your router that has lost either the port-forwarding (NAT) rules, or a firewall on the router or on your server that blocks the trafiic to these ports.

I'll try to reset the NAT rules on the router.

Thanks again.

Reset the router and re-entered the port forwarding...no luck.

Then I set a DMZ to 192.168.1.10 on the router..still no luck.

I still have that annoying icon on the top right of my desktop saying no network connection.

Also, everytime I do an ifconfig, my eth0 has a different HWAddress???

Has my network card got dementia?

Thanks again.

Network-manager will not manage interfaces that you have manually assigned a static IP addrss to in the configuration file, that is why network manager is telling you there is "No Network connection"

Some nvidia chipset motherboards have a BIOS option that causes the MAC address to change on every boot.. that is one possible cause of you changing MAC. If you have an option like that in the BIOS it can easily be disabled.

If your router hasd forwarding enabled the next thing i would look at is local firewall rules..

iptables -L

Hello,

Happy ending!

Many thanks to both of you for taking the time to help me.
So after your comments much googling was done and various fixes attempted, none successful! So I upgraded to debian lenny. Had a problem loading the video driver on reboot "vesa" does not exist, so I did some more googling and ran "aptitude remove xserver-xorg" and then "aptitude install xserver-xorg" and viola!

I rebooted a few times, HWADDRESS and IP address stayed the same, adjusted my /etc/hosts file accordingly......Job done!

Once again, your help is greatly appreciated.

Cheers.