shell - running Xvfb in background on remote linux -

i facing issues xvfb on remote linux. when run command

xvfb :99 & 

i messages on command line initializing built-in extension generic event extension initializing built-in extension shape initializing built-in extension mit-shm initializing built-in extension xinputextension initializing built-in extension xtest initializing built-in extension big-requests initializing built-in extension sync initializing built-in extension xkeyboard initializing built-in extension xc-misc initializing built-in extension security initializing built-in extension xinerama initializing built-in extension xfixes initializing built-in extension render initializing built-in extension randr initializing built-in extension composite initializing built-in extension damage initializing built-in extension mit-screen-saver initializing built-in extension double-buffer initializing built-in extension record initializing built-in extension dpms initializing built-in extension present initializing built-in extension x-resource initializing built-in extension xvideo initializing built-in extension xvideo-motioncompensation initializing built-in extension selinux initializing built-in extension glx

and have suspend using ctrl+c still running in background, writing shell script automate command xvfb :99 & not running in background ! regarding ?

my shell script :

system("sudo yum -y install xvfb"); system("sudo yum -y install firefox"); system("sudo yum -y install imagemagick"); system("xvfb :99 &"); system("export display=:99"); 

instead of & try use below:
issue ctrl+z command after entering xvfb :99
enter bg send process run in background , following keep on running in background.
edit: below should help:

nohup xvfb :99 > /dev/null 2>&1 & 

or nohup xvfb :99 &