i am posting a quick mrtg cfg file which will check for free memory, cpu usage, swap, tcp connections and oracle connections.

these were tested with solaris 10, various linux distros and snmp v1.

## specify mrtg workdir ##
WorkDir: <work dir>
RunAsDaemon: Yes
## interval for mrtg can not be set to less than 5 minutes
Interval: 5
EnableIPv6: no
## change sizes of graphs as needed
XSize[_]: 500
YSize[_]: 200
## change colors to whatever
Colours[_]: DKBLUE#61A0DF,DKBLUE#0000DD,RED#FF0000,DKRED#AB0000

Target[test.oracle]:`<script dir>/oracle-graph.sh`
AbsMax[test.oracle]: 2000
MaxBytes[test.oracle]: 1
Title[test.oracle]: oracle connections - test
PageTop[test.oracle]: <H1>oracle connections - test</H1>
Unscaled[test.oracle]: ymwd
ShortLegend[test.oracle]: .
YLegend[test.oracle]: oracle connection count
## reference tables 1 & 2 in the script
## remember mrtg's limit on two data sources
Legend1[test.oracle]: connections to table 1
Legend2[test.oracle]: connections to table 2
LegendI[test.oracle]: table 1
LegendO[test.oracle]: table 2
Options[test.oracle]: growright,nopercent,gauge,absolute

#################################################################
# oracle-graph.sh script                                        
# #!/bin/bash                                                   
# oracle-graph.sh                                               
# # for this script make sure you have password-less ssh set up 
#                                                               
# DBSERVER=<oracle server ip/hosname>                      
# ssh $DBSERVER ps -fu oracle | grep -c "table 1"               
# ssh $DBSERVER ps -fu oracle | grep -c "table 2"               
#################################################################

## snmp info
## test@localhost:port
## change test to snmp community name
## change localhost to ip name / hostname
## change port to non standard port if needed, if snmp is on standard port then erase this

## cpu graphs
Target[test.cpu]: .1.3.6.1.4.1.2021.10.1.5.1&.1.3.6.1.4.1.2021.10.1.5.1:test@localhost:port
AbsMax[test.cpu]: 10000
Factor[test.cpu]: 0.0
MaxBytes[test.cpu]: 5 
Unscaled[test.cpu]: dwmy
Options[test.cpu]: gauge, absolute, growright, noinfo, nopercent
YLegend[test.cpu]: CPU Load
YTicsFactor[test.cpu]: 0.01
ShortLegend[test.cpu]: - 
LegendI[test.cpu]: 1min ave
LegendO[test.cpu]: 5min ave
Legend1[test.cpu]: 1min ave
Legend2[test.cpu]: 5min ave
Title[test.cpu]: CPU Load ($HOST)
#PageTop[test.cpu]: <H1>CPU Load Average</H1>

## free memory graphs (solaris)
Target[test.mem]: .1.3.6.1.4.1.2021.4.6.0&.1.3.6.1.4.1.2021.4.6.0:test@localhost:port
PageTop[test.mem]: <H1>Free Memory</H1>
Options[test.mem]: nopercent,growright,gauge,noinfo
Title[test.mem]: Free Memory
MaxBytes[test.mem]: 1000000000000
kMG[test.mem]: k,M,G,T,P,X
YLegend[test.mem]: Memory 
#YTicsFactor[test.mem]: 0.1
ShortLegend[test.mem]: bytes
LegendI[test.mem]: Total Free: 
Legend2[test.mem]:  
LegendO[test.mem]: Total Free:
Legend1[test.mem]: Free memory, not including swap, in bytes

## free memory graphs (linux)                                                                            
Target[test.mem]: .1.3.6.1.4.1.2021.4.6.0&.1.3.6.1.4.1.2021.4.6.0:test@localhost:port + .1.3.6.1.4.1.2021.4.14.0&.1.3.6.1.4.1.2021.4.14.0:test@localhost:port + .1.3.6.1.4.1.2021.4.15.0&.1.3.6.1.4.1.2021.4.15.0:test@localhost:port
PageTop[test.mem]: <H1>Free Memory</H1>
Options[test.mem]: nopercent,growright,gauge,noinfo
Title[test.mem]: Free Memory
MaxBytes[test.mem]: 1000000000000
kMG[test.mem]: k,M,G,T,P,X
YLegend[test.mem]: Memory
#YTicsFactor[test.mem]: 0.1
ShortLegend[test.mem]: bytes
LegendI[test.mem]: Total Free:
Legend2[test.mem]:
LegendO[test.mem]: Total Free:
Legend1[test.mem]: Free memory, not including swap, in bytes

## swap graphs
Target[test.swap]: .1.3.6.1.4.1.2021.4.4.0&.1.3.6.1.4.1.2021.4.4.0:test@localhost:port
PageTop[test.swap]: <H1>Swap Memory</H1>
Options[test.swap]: nopercent,growright,gauge,noinfo
Title[test.swap]: Free Memory
MaxBytes[test.swap]: 10000000000000
kMG[test.swap]: k,M,G,T,P,X
YLegend[test.swap]: bytes
ShortLegend[test.swap]: bytes
LegendI[test.swap]:  Free Memory:
LegendO[test.swap]:
Legend1[test.swap]: Swap memory avail, in bytes

## open tcp connections
Target[test.tcpopen]:.1.3.6.1.2.1.6.9.0&.1.3.6.1.2.1.6.9.0:test@localhost:port
Options[test.tcpopen]: nopercent,growright,gauge,noinfo
Title[test.tcpopen]: Open TCP connections
PageTop[test.tcpopen]: <H1>Open TCP connections</H1>
MaxBytes[test.tcpopen]: 1000000
YLegend[test.tcpopen]: # of connections
ShortLegend[test.tcpopen]: connections
LegendI[test.tcpopen]:  Connections:
LegendO[test.tcpopen]:
Legend1[test.tcpopen]: Open TCP connections

any questions – msg me