rsearch-bin: 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/rsearch-bin - from package: 389-ds-base

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

On Debian possible default full paths are:

/usr/bin/rsearch-bin - from package: 389-ds-base

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

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