dúvida no mrtg

galera,

estava vendo em http://people.ee.ethz.ch/~oetiker/webtools/mrtg/pt/squid.html como faço para configurar o mrtg com o squid e surgiram as seguintes duvidas:

-> como faço para iniciar o mrtg??
-> essa configuração:

Target[proxy-hit]: cacheHttpHits&cacheProtoClientHttpRequests<IMG SRC="images/forum/icons/icon_razz.gif">ublic@proxy
Title[proxy-hit]: HTTP Hits
PageTop[proxy-hit]: <H2>proxy Cache Statistics: HTTP Hits / Requests</H2>
Suppress[proxy-hit]: y
LegendI[proxy-hit]: HTTP hits
LegendO[proxy-hit]: HTTP requests
Legend1[proxy-hit]: HTTP hits
Legend2[proxy-hit]: HTTP requests
YLegend[proxy-hit]: perminute
ShortLegend[proxy-hit]: req/min
Options[proxy-hit]: nopercent, perminute, dorelpercent Target[proxy-srvkbinout]: cacheServerInKb&cacheServerOutKb<IMG SRC="images/forum/icons/icon_razz.gif">ublic@proxy
Title[proxy-srvkbinout]: Cache Server Traffic In / Out
PageTop[proxy-srvkbinout]: <H2>Cache Statistics: Server traffic volume (In/Out) </H2>
Suppress[proxy-srvkbinout]: y
LegendI[proxy-srvkbinout]: Traffic In
LegendO[proxy-srvkbinout]: Traffic Out
Legend1[proxy-srvkbinout]: Traffic In
Legend2[proxy-srvkbinout]: Traffic Out
YLegend[proxy-srvkbinout]: per minute
ShortLegend[proxy-srvkbinout]: b/min
kMG[proxy-srvkbinout]: k,M,G,T
kilo[proxy-srvkbinout]: 1024
Options[proxy-srvkbinout]: nopercent, perminute

que esta no site eu devo editar onde: no /etc/mrtg/mrtg.cfg ou no /etc/mrtg/mrtg.ok??
-> é necessário abilitar no ntsysv o snmpd??

Uso o red hat 7.3.
Obrigado.