dzegrep: 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/bin/dzegrep - from package: debian-goodies

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

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