sra-kar: command not found

Have You tried accessing the binary with the full path?

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/sra-kar - from package: sra-toolkit

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