spacecmd: 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 CentOS possible default full paths are:

/usr/bin/spacecmd - from package: spacecmd

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