scsi_ch_swp: 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/scsi_ch_swp - from package: sdparm

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

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