pt-fifo-split: 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 Debian possible default full paths are:

/usr/bin/pt-fifo-split - from package: percona-toolkit

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