keytool: 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 Debian possible default full paths are:

/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/bin/keytool - from package: gcj-4.8-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/jre/bin/keytool - from package: gcj-4.8-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64/bin/keytool - from package: gcj-4.9-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64/jre/bin/keytool - from package: gcj-4.9-jre-headless
/usr/lib/debug/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/keytool - from package: openjdk-7-dbg
/usr/lib/jvm/java-7-openjdk-amd64/bin/keytool - from package: openjdk-7-jre-headless
/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/keytool - from package: openjdk-7-jre-headless

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

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