chsh: 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/bin/chsh - from package: util-linux-ng

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

On Debian possible default full paths are:

/usr/bin/chsh - from package: passwd

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

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