dshbak: 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/dshbak - from package: pdsh

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

On Debian possible default full paths are:

/usr/bin/dshbak - from package: pdsh

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