bdb_recover: 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/sbin/bdb_recover - from package: opensips-db_berkeley

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

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