log connection each minute

Using iRules, you can generate a log entry every time a connection to the associated virtual server is created.

You can also query the ltm to display all current connections (tmsh show sys connection), but be very careful with that command, as it can result in a heartbeat failure due to taking too long to complete, when there are a very large number of connections in the table. The command also accepts filters to limit the output to specific source/dest addresses, age, or connection type.

do you need connection details such as source and destination or only a connection count?

have you tried the commands by themselves yourself? when i run tmsh show sys connection i get

Really display all connections? (y/n)

which will break your script at this stage

a solution seems to be

tmsh -q show sys connection

although doing a grep doesnt do anything for me here, as the last line is: Total records returned: 119, so it would have to be a grep Total i believe

then the second line, why the -c ?

tmsh show ltm node  | grep 'Current Connections'

works for me fine

then again as above for the final command

script becomes (i have thrown in a date / time stamp, feel free to remove)

 !/bin/sh

 script para ejecutar comando cada minuto

echo "$(date)"
tmsh -q show sys connection | grep Total
tmsh show ltm node node_135.208.45.223 | grep 'Current Connections'
tmsh -q show sys connection | grep Total

crontab looks almost fine although you seem to miss a first

/

root/home/root/Mi_script.sh >> /home/root/conexiones.txt

you could do the >> in the script and not in the crontab, perhaps some linux gurus have opinions on this.

Would you not be better monitoring various aspects using an SNMP tool ?