Functions
MLR 3G 2.0
10.11.10
Debugging
The MLR 3G 2.0 offers several tools for analysing problems with network connections.
The "PING" tool allows to send ICMP pings (ping packets). This enables to test, whether a
specific machine is available in the network, easily. The "TRACEROUTE" tool shows the
route of an IP packet to its destination. The "DNS LOOKUP" tool allows to request DNS
information via an IP address or a domain name. The "TCPDUMP" tool allows to record
network packets.
Configuration with the web interface
In order to
send a ping packet
, select in the menu "System" on the page "De-
bugging" the tool "PING" in the drop-down list field, enter the IP address, to
which you want to send the ping packet, or the domain name into the field
"Parameter" and click on "OK". Optionally, you may enter additional parame-
ters before, like -s 300 (sends 300 bytes as payload in ICMP ping) or -c 3 (sends
subsequent 3 pings) for example. The reply will be displayed on the bottom of
the page.
In order to
trace the rout of an IP packet
, select in the menu "System" on the
page "Debugging" the tool "TRACEROUTE" in the drop-down list field, enter
the IP address, to which you want to send the IP packet, or the domain name
into the field "Parameter" and click on "OK". Optionally, you may increase the
standard number of 3 hops by increasing the number of hops to 5 for example
using the parameter "-m 5" before. The reply will be displayed on the bottom
of the page.
In order to
query DNS information
, select in the menu "System" on the page
"Debugging" the tool "DNS LOOKUP" in the drop-down list field, enter the IP
address or domain name to be queried into the field "Parameter" and click on
"OK". If no DNS server has been configured or assigned by an external provider
or router, this query may take up to 40 seconds.
In order to
start recording of network packets
, select in the menu "System" on
the page "Debugging" the tool "TCPDUMP" in the drop-down list field, specify
at least the network device using the parameter "-i" in the field "Parameter"
(e.g. "-i br0" for the LAN interface) and click on "OK". The available network de-
vices can be identified by selecting the link "Show current system state" in the
menu "System" on the page "System data". After starting, the recording will
continue until it is stopped manually or has reached a size of 1 MB. The re-
cording will be displayed immediately after stopping and can be downloaded
as a file using the link "TCPDUMP recording"that will then be displayed. It can
be viewed on an external machine using "tcpdump" or "wireshark".
90
