split: 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/split - from package: coreutils
/usr/bin/split - from package: edk2-tools

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

On Debian possible default full paths are:

/usr/bin/split - from package: coreutils
/usr/lib/plan9/bin/split - from package: 9base
/usr/lib/cmtk/bin/split - from package: cmtk

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

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