Basic Network Troubleshooting

Scroll down further for Windows 16-bit and Linux 32/64-bit instruction



** Test instruction for Windows 32/64-bit (ie: NT, 2K, XP, Vista) **

1. 
   PC #1
2. Go to Start->Run
3. Type in cmd and hit Enter. Command line window appears.
4. Type in IPCONFIG and hit Enter.
5. Record your PC´s IP address, eg: 192.168.1.100 (if it starts with 0, 169 or 165, then your DHCP is not working).
   
   PC #2
6. Go to Start->Run
7. Type in cmd and hit Enter. Command line window appears.
8. Type in IPCONFIG and hit Enter.
9. Record that PC´s IP address, eg: 192.168.1.101 (if it starts with 0, 169 or 165, then your DHCP is not working).
10. Type in PING x.x.x.x (where x.x.x.x is the IP address you recorded from PC #1) and hit Enter.
11. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
    
    Back to PC #1
12. Type in PING y.y.y.y (where y.y.y.y is the IP address you recorded from PC #2) and hit Enter.
13. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
    
    Still not working?
14. On BOTH PCs, type in IPCONFIG /RELEASE and hit Enter.
15. On BOTH PCs, now type in IPCONFIG /RENEW and hit Enter. Wait a few moments as this can happen quickly or slowly.
16. Both PCs should get a new IP address from your router - check with IPCONFIG and Enter again. If not, the fact that a DHCP server could not be found will be returned. Check your router config that DHCP is turned on and configured correctly.
17. Failing all this, specify an IP address manually on both machines, eg: PC #1 can use 192.168.1.10 and PC #2 can use 192.168.1.20, both with a subnet mask of 255.255.255.0 and no gateway or DNS specified.
18. Repeat ping test.
    
    Still not working?
19. On BOTH PCs, type in PING 127.0.0.1 and hit Enter. Do you get a reply? If not, your networking on that PC is stuffed. Suggest re-install.
20. On BOTH PCs, type in IPCONFIG /ALL and post up the output so we can have a look.

Testing sharing for Windows 32/64-bit

1. 
   PC #1
2. At a command prompt, type in NET VIEW \\x.x.x.x and hit Enter (where x.x.x.x is the IP address of the PC #2). You should get a list of available shares. If not, note down the error.
   
   PC #2
3. At a command prompt, type in NET VIEW \\y.y.y.y and hit Enter (where y.y.y.y is the IP address of the PC #1). You should get a list of available shares. If not, note down the error.
4. Post up results.
   
   If the above WORKS
5. Map a network drive manually with NET USE M: \\x.x.x.x\sharename and hit Enter (where x.x.x.x is PC #1 or 2´s IP address and sharename is the name of the share you are trying to access. Change the drive letter if you want.
6. Now type DIR M:\ and see if anything comes back.
7. Post up results.

** Test instruction for Windows 16-bit (ie: 95, 98, ME) **

1. 
   PC #1
2. Go to Start->Run
3. Type in winipcfg and hit Enter. Current network configuration window appears.
4. Record your PC´s IP address, eg: 192.168.1.100 (if it starts with 0, 169 or 165, then your DHCP is not working).
   
   PC #2
5. Go to Start->Run
6. Type in winipcfg and hit Enter. Current network configuration window appears.
7. Record that PC´s IP address, eg: 192.168.1.101 (if it starts with 0, 169 or 165, then your DHCP is not working).
8. Go to Start->Run again.
9. Type in command and hit Enter. Command line window appears.
10. Type in PING x.x.x.x (where x.x.x.x is the IP address you recorded from PC #1) and hit Enter.
11. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
    
    Back to PC #1
12. Go to Start->Run again.
13. Type in command and hit Enter. Command line window appears.
14. Type in PING y.y.y.y (where y.y.y.y is the IP address you recorded from PC #2) and hit Enter.
15. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
    
    Still not working?
16. On BOTH PCs, refer to the network config window you opened with winipcfg and click on RELEASE.
17. On BOTH PCs, refer to the network config window you opened with winipcfg and click on RENEW. Wait a few moments as this can happen quickly or slowly.
18. Both PCs should get a new IP address from your router - the details in the network config window should update. If not, the fact that a DHCP server could not be found will be returned. Check your router config that DHCP is turned on and configured correctly.
19. Failing all this, specify an IP address manually on both machines, eg: PC #1 can use 192.168.1.10 and PC #2 can use 192.168.1.20, both with a subnet mask of 255.255.255.0 and no gateway or DNS specified.
20. Repeat ping test.
    
    Still not working?
21. On BOTH PCs, type in PING 127.0.0.1 and hit Enter. Do you get a reply? If not, your networking on that PC is stuffed. Suggest re-install.
22. On BOTH PCs, copy the info in the network config window that you brought up with winipcfg and post up the output so we can have a look.

** Test instruction for Linux 32/64-bit (eg: Ubuntu) **

NOTE: This instruction assumes GNOME GUI. Adapt to suit KDE.

1. 
   PC #1
2. Press CTRL + SYSREQ (the key with "PrtScn" on it). Alternatively press ALT + F2 and type in gnome-terminal and hit Enter. Terminal (command line) window appears.
3. Type in ifconfig and hit Enter.
4. Record your PC´s IP address, eg: 192.168.1.100 (if it starts with 0, 169 or 165, or is NOT SHOWN then your DHCP is not working).
   
   PC #2
5. Press CTRL + SYSREQ (the key with "PrtScn" on it). Alternatively press ALT + F2 and type in gnome-terminal and hit Enter. Terminal (command line) window appears.
6. Type in ifconfig and hit Enter.
7. Record your PC´s IP address, eg: 192.168.1.101 (if it starts with 0, 169 or 165, or is NOT SHOWN then your DHCP is not working).
8. Type in ping -c4 x.x.x.x (where x.x.x.x is the IP address you recorded from PC #1) and hit Enter.
9. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
   
   Back to PC #1
10. Type in ping -c4 y.y.y.y (where y.y.y.y is the IP address you recorded from PC #2) and hit Enter.
11. If you get reply messages, your network is working. If you get host unreachable, then you have a gateway issue. If you get no reply then it could be firewall or hardware related (or a typo).
    
    Still not working?
12. On BOTH PCs, type in sudo dhclient and hit Enter (you will be prompted for your Admin/root password). Wait a few moments as this can happen quickly or slowly.
13. Both PCs should get a new IP address from your router - check with ifconfig again. If not, the fact that a DHCP server could not be found will be returned. Check your router config that DHCP is turned on and configured correctly.
14. Failing all this, specify an IP address manually on both machines, eg: PC #1 can use 192.168.1.10 and PC #2 can use 192.168.1.20, both with a subnet mask of 255.255.255.0 and no gateway or DNS specified.
15. Repeat ping test.
    
    Still not working?
16. On BOTH PCs, type in ping -c4 127.0.0.1 and hit Enter. Do you get a reply? If not, your networking on that PC is stuffed. Suggest re-install.
17. On BOTH PCs, type in ifconfig and post up the output so we can have a look.

Testing sharing for Linux 32/64-bit

1. 
   PC #1
2. Ensure SAMBA is installed with sudo apt-get install samba smbclient smbfs and hit Enter. Enter your admin password and wait until the installation process is completed.
3. Is Samba was NOT installed and you've now just finished installing it, type in sudo nano /etc/samba/smb.conf and hit Enter. Edit the line that reads security = user to security = share and then save and exit the file. Restart Samba using sudo /etc/init.d/samba restart and hit Enter. Enter your admin/root password when prompted.
4. At a terminal prompt, type in smbclient -L x.x.x.x and hit Enter (where x.x.x.x is the IP address of the PC #2). You should get a list of available shares. If not, note down the error.
   
   PC #2
5. Ensure SAMBA is installed with sudo apt-get install samba smbclient smbfs and hit Enter. Enter your admin password and wait until the installation process is completed.
6. Is Samba was NOT installed and you've now just finished installing it, type in sudo nano /etc/samba/smb.conf and hit Enter. Edit the line that reads security = user to security = share and then save and exit the file. Restart Samba using sudo /etc/init.d/samba restart and hit Enter. Enter your admin/root password when prompted.
7. At a command prompt, type in smbclient -L y.y.y.y and hit Enter (where y.y.y.y is the IP address of the PC #1). You should get a list of available shares. If not, note down the error.
8. Post up results.
   
   If the above WORKS
9. Mount a share manually by creating an empty directory somewhere, eg: mkdir /tmp/myshare to mount on and then type in sudo mount -t smbfs //x.x.x.x/sharename /tmp/myshare and hit Enter (where x.x.x.x is PC #1 or 2´s IP address and sharename is the name of the share you are trying to access. Change the mount point if you want.
10. Now type ls -l /tmp/myshare and see if anything comes back.
11. Post up results.

 

Above posts copied from an existing thread. If someone that's been doing so wants to copy it into the wiki, that'd be great.

-Nick