epmd: 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/epmd - from package: erlang-erts
/usr/lib64/erlang/bin/epmd - from package: erlang-erts
/usr/lib64/erlang/erts-5.8.5/bin/epmd - from package: erlang-erts

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

On Debian possible default full paths are:

/usr/bin/epmd - from package: erlang-base-hipe
/usr/lib/erlang/bin/epmd - from package: erlang-base-hipe
/usr/lib/erlang/erts-6.2/bin/epmd - from package: erlang-base-hipe
/usr/bin/epmd - from package: erlang-base
/usr/lib/erlang/bin/epmd - from package: erlang-base
/usr/lib/erlang/erts-6.2/bin/epmd - from package: erlang-base
/usr/lib/debug/usr/lib/erlang/erts-6.2/bin/epmd - from package: erlang-dbg

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

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