skipredundant: 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/skipredundant - from package: emboss

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

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