nsdb-annotate: 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/sbin/nsdb-annotate - from package: fedfs-utils-admin

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