fbo-drawbuffers2-colormask: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/piglit/bin/fbo-drawbuffers2-colormask - from package: piglit

You may install the required package with command yum install {package}
Error in other languages:
fbo-drawbuffers2-colormask: bevel nie gevind nie
fbo-drawbuffers2-colormask: comandă negăsită
fbo-drawbuffers2-colormask: comando não encontrado
fbo-drawbuffers2-colormask: commande introuvable
fbo-drawbuffers2-colormask: command not found
fbo-drawbuffers2-colormask: käsku ei ole
fbo-drawbuffers2-colormask: không tìm thấy lệnh
fbo-drawbuffers2-colormask: komanda nerasta
fbo-drawbuffers2-colormask: Kommando nicht gefunden.
fbo-drawbuffers2-colormask: kommandot finns inte
fbo-drawbuffers2-colormask: komut yok
fbo-drawbuffers2-colormask: nie znaleziono polecenia
fbo-drawbuffers2-colormask: níor aimsíodh an t-ordú
fbo-drawbuffers2-colormask: no se encontró la orden
fbo-drawbuffers2-colormask: no s'ha trobat l'ordre
fbo-drawbuffers2-colormask: opdracht niet gevonden
fbo-drawbuffers2-colormask: parancs nem található
fbo-drawbuffers2-colormask: perintah tidak ditemukan
fbo-drawbuffers2-colormask: príkaz nenájdený
fbo-drawbuffers2-colormask: příkaz nenalezen
fbo-drawbuffers2-colormask: команда не найдена
fbo-drawbuffers2-colormask: командата не е открита
fbo-drawbuffers2-colormask: 命令找不到
fbo-drawbuffers2-colormask: コマンドが見つかりません