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(New page: When debugging a School server connectivity issue, there are a number of tools to use. These require an ssh connection (or console access) to the school server. ==Are the Interfaces ...)
 
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<noinclude>{{TOCright}}
[[category:SchoolServer]]
[[Category:Network]]
</noinclude>
When debugging a [[School server]] connectivity issue, there are a number of tools to use. These require an ssh connection (or console access) to the school server.
When debugging a [[School server]] connectivity issue, there are a number of tools to use. These require an ssh connection (or console access) to the school server.

* A useful discussion for LAN/WAN debugging, http://lists.laptop.org/pipermail/server-devel/2010-July/004995.html


==Are the Interfaces Present==
==Are the Interfaces Present==


First, check to see what the schoolserver OS thinks it's network interfaces are:

===ifconfig===
You can check on the interfaces using the <tt>ifconfig</tt> command:
You can check on the interfaces using the <tt>ifconfig</tt> command:


ifconfig
/sbin/ifconfig
ifconfig eth0
/sbin/ifconfig eth0


A typical ifconfig output (for a machine with a single [[Active Antenna]] and one wired network interface) is:
A typical ifconfig output (for a machine with two [[Active Antenna]] and one wired network interface) is:


br0 Link encap:Ethernet HWaddr 00:50:43:28:0A:B7
'''insert dump here'''
inet addr:172.18.16.1 Bcast:172.18.31.255 Mask:255.255.240.0
inet6 addr: fe80:0:0:10::1/64 Scope:Link
inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:64 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:12653 (12.3 KiB)
br1 Link encap:Ethernet HWaddr 00:50:43:28:0A:B8
inet addr:172.18.32.1 Bcast:172.18.47.255 Mask:255.255.240.0
inet6 addr: fe80:0:0:11::1/64 Scope:Link
inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:12 errors:0 dropped:0 overruns:0 frame:0
TX packets:75 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:2352 (2.2 KiB) TX bytes:15080 (14.7 KiB)
br2 Link encap:Ethernet HWaddr 00:00:00:00:00:00
inet addr:172.18.48.1 Bcast:172.18.63.255 Mask:255.255.240.0
inet6 addr: fe80:0:0:12::1/64 Scope:Link
inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:66 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:12911 (12.6 KiB)
eth0 Link encap:Ethernet HWaddr 00:19:5B:68:9D:4E
inet addr:172.16.0.53 Bcast:172.16.0.255 Mask:255.255.255.0
inet6 addr: fe80::219:5bff:fe68:9d4e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:283 errors:0 dropped:0 overruns:0 frame:0
TX packets:234 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:31477 (30.7 KiB) TX bytes:31716 (30.9 KiB)
Interrupt:17 Base address:0x2000
eth1 Link encap:Ethernet HWaddr 00:40:63:E9:99:9B
inet addr:172.18.0.1 Bcast:172.18.15.255 Mask:255.255.240.0
inet6 addr: fe80::1/64 Scope:Link
inet6 addr: fe80::240:63ff:fee9:999b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:76 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:13857 (13.5 KiB)
Interrupt:18 Base address:0xf800
eth2 Link encap:Ethernet HWaddr 00:50:43:28:0A:B7
inet6 addr: fe80::250:43ff:fe28:ab7/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:36 errors:0 dropped:0 overruns:0 frame:0
TX packets:1118 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:8591 (8.3 KiB) TX bytes:130628 (127.5 KiB)
eth3 Link encap:Ethernet HWaddr 00:50:43:28:0A:B8
inet6 addr: fe80::250:43ff:fe28:ab8/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:29 errors:0 dropped:0 overruns:0 frame:0
TX packets:330 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5429 (5.3 KiB) TX bytes:58058 (56.6 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:1 errors:0 dropped:0 overruns:0 frame:0
TX packets:1 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:76 (76.0 b) TX bytes:76 (76.0 b)
msh0 Link encap:Ethernet HWaddr 00:50:43:28:0A:B7
inet6 addr: fe80::250:43ff:fe28:ab7/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:36 errors:0 dropped:0 overruns:0 frame:0
TX packets:1118 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:8591 (8.3 KiB) TX bytes:130628 (127.5 KiB)
msh1 Link encap:Ethernet HWaddr 00:50:43:28:0A:B8
inet6 addr: fe80::250:43ff:fe28:ab8/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:29 errors:0 dropped:0 overruns:0 frame:0
TX packets:330 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5429 (5.3 KiB) TX bytes:58058 (56.6 KiB)

===iwconfig===


The details of the wireless interfaces can be seen using <tt>iwconfig</tt> :
The details of the wireless interfaces can be seen using <tt>iwconfig</tt> :


iwconfig
/sbin/iwconfig
iwconfig msh0
/sbin/iwconfig msh0


A typical output for this command (when using two [[Active Antenna]]) is:
'''route'''

lo no wireless extensions.
eth1 no wireless extensions.
eth0 no wireless extensions.
br0 no wireless extensions.
br1 no wireless extensions.
br2 no wireless extensions.
eth2 IEEE 802.11b/g ESSID:"school-mesh-0" Nickname:"schoolserver"
Mode:Ad-Hoc Frequency:2.412 GHz Cell: 00:33:33:FF:28:0A
Bit Rate:2 Mb/s Tx-Power=13 dBm
Retry limit:8 RTS thr=2347 B Fragment thr=2346 B
Power Management:off
Link Quality=100/100 Signal level=-256 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:3932
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
msh0 IEEE 802.11b/g ESSID:"mesh" Nickname:"Mesh"
Mode:Repeater Frequency:2.412 GHz Bit Rate:2 Mb/s Tx-Power=13 dBm
Retry limit:8 RTS thr=2347 B Fragment thr=2346 B
Power Management:off
Link Quality=100/100 Signal level=-256 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:3936
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
eth3 IEEE 802.11b/g ESSID:"school-mesh-1" Nickname:"schoolserver"
Mode:Ad-Hoc Frequency:2.462 GHz Cell: 00:02:00:2A:09:00
Bit Rate:2 Mb/s Tx-Power=13 dBm
Retry limit:8 RTS thr=2347 B Fragment thr=2346 B
Power Management:off
Link Quality=100/100 Signal level=-256 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:2698
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
msh1 IEEE 802.11b/g ESSID:"mesh" Nickname:"Mesh"
Mode:Repeater Frequency:2.462 GHz Bit Rate:2 Mb/s Tx-Power=13 dBm
Retry limit:8 RTS thr=2347 B Fragment thr=2346 B
Power Management:off
Link Quality=100/100 Signal level=-256 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:2703
Tx excessive retries:0 Invalid misc:0 Missed beacon:0


===route===

''Discuss the use of the route command in debugging...''


==Are Basic Services Running==
==Are Basic Services Running==
Line 25: Line 177:
sudo service dhcpd status
sudo service dhcpd status
sudo service named status
sudo service named status

===DHCP===


If there are laptop running on the mesh, there will be DHCP traffic associated with each one every five minutes. This may be watched using:
If there are laptop running on the mesh, there will be DHCP traffic associated with each one every five minutes. This may be watched using:
Line 30: Line 184:
sudo tail -f /var/log/messages
sudo tail -f /var/log/messages


===DNS===
'''host and dig'''

''host and dig''


==Watching the Packets Go By==
==Watching the Packets Go By==
Line 47: Line 203:
You can enable additional debugging output from the driver using:
You can enable additional debugging output from the driver using:


echo 0x136184 > /sys/module/libertas/parameters/libertas_debu
echo 0x136184 > /sys/module/libertas/parameters/libertas_debug

Latest revision as of 19:11, 9 July 2010

When debugging a School server connectivity issue, there are a number of tools to use. These require an ssh connection (or console access) to the school server.

Are the Interfaces Present

First, check to see what the schoolserver OS thinks it's network interfaces are:

ifconfig

You can check on the interfaces using the ifconfig command: 

/sbin/ifconfig
/sbin/ifconfig eth0

A typical ifconfig output (for a machine with two Active Antenna and one wired network interface) is: 

br0      Link encap:Ethernet  HWaddr 00:50:43:28:0A:B7  
         inet addr:172.18.16.1  Bcast:172.18.31.255  Mask:255.255.240.0
         inet6 addr: fe80:0:0:10::1/64 Scope:Link
         inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:0 errors:0 dropped:0 overruns:0 frame:0
         TX packets:64 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:0 
         RX bytes:0 (0.0 b)  TX bytes:12653 (12.3 KiB)

br1      Link encap:Ethernet  HWaddr 00:50:43:28:0A:B8  
         inet addr:172.18.32.1  Bcast:172.18.47.255  Mask:255.255.240.0
         inet6 addr: fe80:0:0:11::1/64 Scope:Link
         inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:12 errors:0 dropped:0 overruns:0 frame:0
         TX packets:75 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:0 
         RX bytes:2352 (2.2 KiB)  TX bytes:15080 (14.7 KiB)

br2      Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
         inet addr:172.18.48.1  Bcast:172.18.63.255  Mask:255.255.240.0
         inet6 addr: fe80:0:0:12::1/64 Scope:Link
         inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:0 errors:0 dropped:0 overruns:0 frame:0
         TX packets:66 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:0 
         RX bytes:0 (0.0 b)  TX bytes:12911 (12.6 KiB)

eth0     Link encap:Ethernet  HWaddr 00:19:5B:68:9D:4E  
         inet addr:172.16.0.53  Bcast:172.16.0.255  Mask:255.255.255.0
         inet6 addr: fe80::219:5bff:fe68:9d4e/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:283 errors:0 dropped:0 overruns:0 frame:0
         TX packets:234 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:31477 (30.7 KiB)  TX bytes:31716 (30.9 KiB)
         Interrupt:17 Base address:0x2000 

eth1     Link encap:Ethernet  HWaddr 00:40:63:E9:99:9B  
         inet addr:172.18.0.1  Bcast:172.18.15.255  Mask:255.255.240.0
         inet6 addr: fe80::1/64 Scope:Link
         inet6 addr: fe80::240:63ff:fee9:999b/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:0 errors:0 dropped:0 overruns:0 frame:0
         TX packets:76 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:0 (0.0 b)  TX bytes:13857 (13.5 KiB)
         Interrupt:18 Base address:0xf800 

eth2     Link encap:Ethernet  HWaddr 00:50:43:28:0A:B7  
         inet6 addr: fe80::250:43ff:fe28:ab7/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:36 errors:0 dropped:0 overruns:0 frame:0
         TX packets:1118 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:8591 (8.3 KiB)  TX bytes:130628 (127.5 KiB)

eth3     Link encap:Ethernet  HWaddr 00:50:43:28:0A:B8  
         inet6 addr: fe80::250:43ff:fe28:ab8/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:29 errors:0 dropped:0 overruns:0 frame:0
         TX packets:330 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:5429 (5.3 KiB)  TX bytes:58058 (56.6 KiB)

lo       Link encap:Local Loopback  
         inet addr:127.0.0.1  Mask:255.0.0.0
         inet6 addr: ::1/128 Scope:Host
         UP LOOPBACK RUNNING  MTU:16436  Metric:1
         RX packets:1 errors:0 dropped:0 overruns:0 frame:0
         TX packets:1 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:0 
         RX bytes:76 (76.0 b)  TX bytes:76 (76.0 b)

msh0     Link encap:Ethernet  HWaddr 00:50:43:28:0A:B7  
         inet6 addr: fe80::250:43ff:fe28:ab7/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:36 errors:0 dropped:0 overruns:0 frame:0
         TX packets:1118 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:8591 (8.3 KiB)  TX bytes:130628 (127.5 KiB)

msh1     Link encap:Ethernet  HWaddr 00:50:43:28:0A:B8  
         inet6 addr: fe80::250:43ff:fe28:ab8/64 Scope:Link
         UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
         RX packets:29 errors:0 dropped:0 overruns:0 frame:0
         TX packets:330 errors:0 dropped:0 overruns:0 carrier:0
         collisions:0 txqueuelen:1000 
         RX bytes:5429 (5.3 KiB)  TX bytes:58058 (56.6 KiB)

iwconfig

The details of the wireless interfaces can be seen using iwconfig : 

/sbin/iwconfig
/sbin/iwconfig msh0

A typical output for this command (when using two Active Antenna) is: 

lo       no wireless extensions.

eth1     no wireless extensions.

eth0     no wireless extensions.

br0      no wireless extensions.

br1      no wireless extensions.

br2      no wireless extensions.

eth2     IEEE 802.11b/g  ESSID:"school-mesh-0"  Nickname:"schoolserver"
         Mode:Ad-Hoc  Frequency:2.412 GHz  Cell: 00:33:33:FF:28:0A   
         Bit Rate:2 Mb/s   Tx-Power=13 dBm   
         Retry limit:8   RTS thr=2347 B   Fragment thr=2346 B   
         Power Management:off
         Link Quality=100/100  Signal level=-256 dBm  Noise level=-96 dBm
         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:3932
         Tx excessive retries:0  Invalid misc:0   Missed beacon:0

msh0     IEEE 802.11b/g  ESSID:"mesh"  Nickname:"Mesh"
         Mode:Repeater  Frequency:2.412 GHz  Bit Rate:2 Mb/s   Tx-Power=13 dBm   
         Retry limit:8   RTS thr=2347 B   Fragment thr=2346 B   
         Power Management:off
         Link Quality=100/100  Signal level=-256 dBm  Noise level=-96 dBm
         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:3936
         Tx excessive retries:0  Invalid misc:0   Missed beacon:0

eth3     IEEE 802.11b/g  ESSID:"school-mesh-1"  Nickname:"schoolserver"
         Mode:Ad-Hoc  Frequency:2.462 GHz  Cell: 00:02:00:2A:09:00   
         Bit Rate:2 Mb/s   Tx-Power=13 dBm   
         Retry limit:8   RTS thr=2347 B   Fragment thr=2346 B   
         Power Management:off
         Link Quality=100/100  Signal level=-256 dBm  Noise level=-96 dBm
         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:2698
         Tx excessive retries:0  Invalid misc:0   Missed beacon:0

msh1     IEEE 802.11b/g  ESSID:"mesh"  Nickname:"Mesh"
         Mode:Repeater  Frequency:2.462 GHz  Bit Rate:2 Mb/s   Tx-Power=13 dBm   
         Retry limit:8   RTS thr=2347 B   Fragment thr=2346 B   
         Power Management:off
         Link Quality=100/100  Signal level=-256 dBm  Noise level=-96 dBm
         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:2703
         Tx excessive retries:0  Invalid misc:0   Missed beacon:0


route

Discuss the use of the route command in debugging...

Are Basic Services Running

You can check on the status of the basic services (DHCP, DNS) using: 

sudo service dhcpd status
sudo service named status

DHCP

If there are laptop running on the mesh, there will be DHCP traffic associated with each one every five minutes. This may be watched using: 

sudo tail -f /var/log/messages

DNS

host and dig

Watching the Packets Go By

You can take a look at the packets traveling over an interface (in this case school-mesh-0) using the tcpdump command: 

/sbin/tcpdump -i msh0

Turning On Additional Wireless Mesh Debugging

You can find out specific about the wireless mesh software drivers being used by using ethtool: 

/sbin/ethtool -i msh0

You can enable additional debugging output from the driver using: 

echo 0x136184 > /sys/module/libertas/parameters/libertas_debug
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