[CONTRIB] DHCP Pool usage

RouterOS Scripting
1

I got tired of not knowing when I was running low on DHCP addresses so I wrote this little bit for our routers.
This is a basic script and my first time sharing. I have tested it on v2.9.42 and v3rc7


\

WarnAt needs to be at what percentage you want to be warned you are running out of IP addresses.

:local WarnAt 10

Set to your e-mail address.

:local EMail me@mydomain.com

Set to the name of your DHCP pool

:local Pool dhcp_pool1

:local ip [:tostr [ip pool get $Pool ranges]]
:local Start [:pick $ip 0 [:find $ip "-"]]
:local Stop [:pick $ip ([:find $ip "-"] + 1) 31]
:local Total ($Stop - $Start)
:local Identity [/system identity get name]
:local Used [/ip dhcp-server lease print count-only]
:local Available ($Total - $Used)
:local Perc (($Available* 100) / $Total)
:local Subject ($Identity . " DHCP pool is at " . $Perc . "%")
:local Body ("Out of " . $Total . " addresses you have " . $Available . " available")
:if ($Perc <= $WarnAt) do={
/tool e-mail send to=$EMail subject=$Subject body=$Body
}

filtering leases by print (DHCP-SERVER)
2

This script is very useful, thanks.

Just one thing, it calculates one less IP in the range than is really defined.

I’m not that sure what this line means;

:local Stop [:pick $ip ([:find $ip “-”] + 1) 31]

3

Thank you for noticing that hilton.

Here is my revised script that fixes that issue as well as adds the ability to use the script when running multiple dhcp servers.

Tested on v3.7

# WarnAt needs to be at what percentage you want to be warned you are running out of IP addresses.
:local WarnAt 10
#Name of DHCP Pool you want to monitor
:local DHCPPoolName dhcp_pool1
#Your Email to notify you when running out of available ip's
:local Email my@email.com
#Your mail server ip address
:local EmailServer 0.0.0.0

#Declare Variable
:local Total

:foreach i in=[/ip pool get $DHCPPoolName ranges] do={
#Get the DHCP pool range and put into a string.
:local range [:tostr $i]
#Get the Start address of the range
:local Start [:pick $range 0 [:find $range "-"]]
#Get the End address of the range
:local Stop [:pick $range ([:find $range "-"] + 1) 31]
#Calculate how many IP's are in the Pool by subtracting the end address and the start address and add one.
:local ip ($Stop - $Start +1 )
#Save the size of the pool to Total
:set Total ($ip + $Total)
}

#Get the name of the Server that is using the Pool
:local Server [/ip dhcp-server get [/ip dhcp-server find address-pool="$DHCPPoolName"] name]
#Get the number of IP address's used in the pool
:local Used [/ip dhcp-server lease print count-only where server=[/ip dhcp-server get [/ip dhcp-server find address-pool=$DHCPPoolName] name]]
#Subtract used from total to get available
:local Available ($Total - $Used)
#Calculate percentage IP's available
:local Perc (($Available * 100) / $Total)
#Setup e-mail
:local Subject ([/system identity get name] . " DHCP pool is at $Perc")
:local Body ("Out of $Total addresses you have $Available available")

#Send out Email when available ip's percentage is below or equal to warnat
:if ($Perc <= $WarnAt) do={
  /tool e-mail send to=$Email subject=$Subject body=$Body server=$EmailServer
}
:log info $Body
4

Thanks a lot!

5

Can someone please provide a script to send an email when an IP is given out by a DHCP server/pool? Thanks.

6

Can someone please provide a script to send an email when an IP is given out by a DHCP server/pool? Thanks.

I recall seeing a script like this somewhere and I also need it now. Does someone have it?

7

http://wiki.mikrotik.com/wiki/Log_Parser_-_Event_Trigger_Script