gencnval: 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/gencnval - from package: icu

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

On Debian possible default full paths are:

/usr/bin/gencnval - from package: icu-devtools

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