gensystemid: 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/bin/gensystemid - from package: mrepo

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