drbdlinks: command not found

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/sbin/drbdlinks - from package: drbdlinks

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/sbin/drbdlinks - from package: drbdlinks

You may install the required package with command apt-get install {package}

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