pt-table-checksum: 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-table-checksum - from package: percona-toolkit

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