dgscat-int64: 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 Debian possible default full paths are:

/usr/lib/debug/usr/bin/dgscat-int64 - from package: ptscotch-dbg
/usr/bin/dgscat-int64 - from package: ptscotch

You may install the required package with command apt-get install {package}
Error in other languages:
dgscat-int64: bevel nie gevind nie
dgscat-int64: comandă negăsită
dgscat-int64: comando não encontrado
dgscat-int64: commande introuvable
dgscat-int64: command not found
dgscat-int64: käsku ei ole
dgscat-int64: không tìm thấy lệnh
dgscat-int64: komanda nerasta
dgscat-int64: Kommando nicht gefunden.
dgscat-int64: kommandot finns inte
dgscat-int64: komut yok
dgscat-int64: nie znaleziono polecenia
dgscat-int64: níor aimsíodh an t-ordú
dgscat-int64: no se encontró la orden
dgscat-int64: no s'ha trobat l'ordre
dgscat-int64: opdracht niet gevonden
dgscat-int64: parancs nem található
dgscat-int64: perintah tidak ditemukan
dgscat-int64: príkaz nenájdený
dgscat-int64: příkaz nenalezen
dgscat-int64: команда не найдена
dgscat-int64: командата не е открита
dgscat-int64: 命令找不到
dgscat-int64: コマンドが見つかりません