ircd-hybrid: 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/sbin/ircd-hybrid - from package: ircd-hybrid

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

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