Automatically Change Frequencies To Compensate for Weather

RouterOS Scripting
21

Nice.
Extending the script for setting tx-power and watching the remote-rx with an option to set the power without reconnect we will have a simple atpc.
Is there a way to set tx-power without loosing the connection?

22

Unfortunately, no. Any changes to tx-power (from either end) cause the wireless interface to stop and restart, resulting in a reconnect by the clients. Luckily, the reconnect only takes a split second.

23

For those considering trying the same thing, I have been using wanned’s script since early May and my system has been running great.
Uptime is better than 99% on any given day.

Here are the settings I use:

:local dbm0snr1either2 0
:local mindbm -87
:local minsnr 12
:local freq1 5620
:local freq2 5660
:local checkdelay 4
:local samplescount 5

As I expected, it turned out to be much easier and cheaper than installing bigger antennas as some suggested.

24

You only change the frequency from 5620 to 5660 and that makes enough difference to solve your ducting/over water wierdness issues?

25

I don’t think it’s a ducting issue. I think it’s a tide/reflection issue in my case, and, yes, it works.

26

This script don’t working on ROS 5.x, any modifications to get it work ?

27

ManUtd,

Likewise, I could not make this script work (using ROS 5.22).
I spent a long time with this script, trying to get it to work.
Finally I found line 22 contained an error, OR old code / syntax that now no longer works.

      :set avgdbm ($avgdbm+[:pick [/int wir reg get [find interface=$wlanname] signal-strength] 0 ([:find [/int wir reg get [find interface=$wlanname] signal-strength] @]-3)])

The “@” symbol does not seem to belong (there’s no reference to it in the scripting manual) - what is it’s purpose?
Also, the “-3” at the end of the line does not make sense.

With the following changes to this line, it works really well:

      :set avgdbm ($avgdbm+[:pick [/int wir reg get [find interface=$wlanname] signal-strength] 0 ([:find [/int wir reg get [find interface=$wlanname] signal-strength]]3)])
28

There is absolutely nothing wrong with that line, at least up through version 5.14. If you understood the scripting :pick and :find commands, you would realize that should not be removed.

The :pick command is taking a sub string from the signal strength result which looks like “-61dBm@54Mbps”
0 is the beginning of the string
The pick command will take the number of characters from that string equal to the numerical location of the “@” symbol minus 3 characters, resulting in a value of just -61 in our example.

I just copied and pasted the following into a cmdlin on version 5.14 and saw the expected result:

:put [:pick [/int wir reg get [find interface=wlan1] signal-strength] 0 ([:find [/int wir reg get [find interface=wlan1] signal-strength] @] -3)]

What “works really well” now is not what was intended and will have very undesirable results.

Your modifications actually break the :find command and result in a static :pick from 0 to 3. That appears to work correctly, unless you get a signal-strength below -99, in which case your modification will falsely report only the first two digits (i.e. -10 instead of -101). In cases of weak signal sensing, this is critical not to misread those values. If you have forced clients into a signal strength range that absolutely rules out the possibility of -100 or worse signals, then feel free to shorten that line further as follows:

:set avgdbm ($avgdbm+[:pick [/int wir reg get [find interface=$wlanname] signal-strength] 0 3)])
29

Hey John, are you free to chat about a similar, but different version of this type of problem? Happy to pay for your services. ben@lup.com.au