asterisk_validate() {
    local rc

    check_binary $OCF_RESKEY_binary
    check_binary pgrep

    if [ -n "$OCF_RESKEY_monitor_sipuri" ]; then
        check_binary sipsak
    fi

    if [ ! -f $OCF_RESKEY_config ]; then
        ocf_log err "Config $OCF_RESKEY_config doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    getent passwd $OCF_RESKEY_user >/dev/null 2>&1
    rc=$?
    if [ $rc -ne 0 ]; then
        ocf_log err "User $OCF_RESKEY_user doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    getent group $OCF_RESKEY_group >/dev/null 2>&1
    rc=$?
    if [ $rc -ne 0 ]; then
        ocf_log err "Group $OCF_RESKEY_group doesn't exist"
        return $OCF_ERR_INSTALLED
    fi

    true
}