srm: 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 CentOS possible default full paths are:

/usr/bin/srm - from package: srm

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/srm - from package: secure-delete

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

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