vcf-subset: 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/bin/vcf-subset - from package: vcftools

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

On Debian possible default full paths are:

/usr/bin/vcf-subset - from package: vcftools

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