dumpLinks: 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/dumpLinks - from package: cjdns-tools

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

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