Here’s the scenario:
RB433AH with 2xR5H. One radio connects to our backbone with a 31dBi dish. One radio provides wireless service via 17dBi sectoral. Dish has 1.2m of LMR400. Sectoral has 1m of LMR400.
Power is provided via a solar panel and 105AH battery. I’ve never had problems with this combo until this past week.
I run the voltage monitor script and the results are emailed to me each night.
The Routerboard runs Hotspot and athenticates users against User Manager that’s located on another RB some distance away.
This past week I’ve noticed that the input power’s been dropping to 12.4V (or lower) for no reason. Until this week there was a pretty steady cycle of dropping down to around 12.5V during the night and then going back to 13V during the day when the solar panel charges the battery. Even after 5 days of cloud, the night time voltage never dropped below 12.5V
On Saturday evening, clients started disconnecting for no reason.
When I logged into the unit I saw the voltage was down to 12.2V and links that were once sitting at -72 were down to -85 or worse.
When I checked Hotspot - Hosts I saw there were over 30,000 hosts listed 
I rebooted the routerboard and watched as the hosts immediately reconnected - from the internet side. I also watched the voltage drop as more and more users connected.
I then went into Hotspot - IP Bindings and disabled each radio that was listed until the number of connecting hosts stopped.
After that I rebooted the routerboard, went to Hotspot - Hosts and saw there were only a couple of hosts listed. I then re-enabled the previously disabled hosts in IP Bindings and left the “problem” disabled.
It wasn’t long before the client called and wanted to know why his downloads had stopped. I asked him what download manager he was using and he said it was Vuse.
It turns out he’s got hundreds (literally) of movies, songs, tv shows etc downloading at the same time with each one getting maybe 0.1kbps or 0.2kbps.
When I suggested to him that he maybe limit the number of concurrent downloads to (let’s say) 5 and that he get those down before proceeding with the next, his comment was “I get uncapped internet and I can do what I want”.
We’ve sent him our standard “abuse of network” letter and I’m blocking his radio’s MAC address until he sorts his issues out. This one guy was causing 40 other people who connect to the same AP problems.
I must add at this point that input power on the radio jumped from 12.2V back to 12.5V as soon as we blocked this guy.
My first question has to be: Can somebody please explain to me why the board would use so much extra power to route IP packets? This is supposed to be a powerful router. I’m truly surprised that it’s having a bit of a meltdown under these conditions.
Secondly, any ideas what I can do to stop this “overflow” from happening again? Is there a way to limit the number of Hotspot Hosts talking to one MAC address?
I am currently shaping the guy’s traffic as follows:
/ ip firewall mangle
add chain=prerouting protocol=tcp dst-port=80 action=mark-connection
new-connection-mark=http_conn passthrough=yes
add chain=prerouting connection-mark=http_conn action=mark-packet
new-packet-mark=http passthrough=no
add chain=prerouting p2p=all-p2p action=mark-connection
new-connection-mark=p2p_conn passthrough=yes
add chain=prerouting connection-mark=p2p_conn action=mark-packet
new-packet-mark=p2p passthrough=no
add chain=prerouting action=mark-connection new-connection-mark=other_conn
passthrough=yes
add chain=prerouting connection-mark=other_conn action=mark-packet
new-packet-mark=other passthrough=no/ queue simple
add name=“main” target-addresses=192.168.x.7/32 max-limit=128000/384000
add name=“http” packet-marks=http max-limit=64000/256000 priority=1
add name=“p2p” packet-marks=p2p max-limit=32000/64000 priority=8
add name=“other” packet-marks=other max-limit=32000/64000 priority=4