Mobile interface
U
SER
G
UIDE
94
set rtr type ipIcmpEcho dst-addr <ip_addr>
set rtr frequency 15
set rtr timeout 2000
set rtr lifetime 0
set rtr start-time immediately
set trigger gprs up set rtr on
set trigger gprs down set rtr off
It is also possible to use the
bfdping
command when there is no available IP address to send ICMP
packets:
set gprs idle 0
set gprs rx-idle 120
set trigger timer-tick bfdping
–
i ppp0
set trigger gprs up set timer-tick 15
set trigger gprs down set no-timer-tick
Whenever a GPRS session is activated, a periodic timer of 15 seconds starts and after this the
bfdping
command is executed. This command forces the transmission of a UDP packet which has
as destination address the IP address associated with the GPRS interface, thus the first router of the
network (the first hop) must send it back. If this packet is not received the timeout of the GPRS
session (rx-idle 120) and its consequent re-activation occur.
The
gprs-keep-alive
command can be used to send an ICMP request (ping) to the address
associated with the GPRS interface. In order to control the connection, the command sends it at
regular and configurable intervals.
set trigger gprs up gprs-keep-alive [-k <Freq_sec>]
The
-k <freq_sec>
parameter is optional; the default value is 60 seconds. Whenever a GPRS
session is activated this command forces transmission of a UDP packet which has as destination
address the one associated with GPRS interface. The lack of reply causes timeout of the GPRS
session and its consequent re-activation.
GPRS
SESSION CONTROL
By verifying the GPRS configuration it is possible to activate a connection using the commands “
set
gprs
”
7
without executing GPRS triggers.
The command:
gprsping <ip-address>
activates a GPRS session and executes a series of ICMP packets to a specified IP address without
executing “
GPRS up
” and “
GPRS down
” triggers.
In case of positive test the output is the following:
root@IMOLA>
gprsping 85.34.166.21
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-
When setting the GPRS parameters, it is advisable the insertion of the command “
set gprs pwroff-modem
” for a correct execution of the command gprsping (except for 2XXX models).
