CentOS7 turn off yum automatic download update

CentOS7 the default Yum automatically downloads updates after the installation is minimized, which is not required for many production systems and can be manually closed

[Root@engine cron.weekly]# Cd/etc/yum
[Root@engine yum]# ls
FSSNAP.D pluginconf.d protected.d VARs version-groups.conf yum-cron.conf

Edit yum-cron.conf to change download_updates = yes to No

[Root@engine yum]# Cat yum-cron.conf
[Commands]
# What kind of update to use:
# default = Yum Upgrade
# security = Yum--security upgrade
# security-severity:critical = Yum--sec-severity=critical upgrade
# minimal = Yum--bugfix upgrade-minimal
# minimal-security = Yum--security upgrade-minimal
# minimal-security-severity:critical =--sec-severity=critical Upgrade-minimal
Update_cmd = Default


# Whether A message should is emitted when updates are available,
# were downloaded, or applied.
Update_messages = yes


# Whether updates should is downloaded when they are.
Download_updates = yes


# Whether updates should is applied when they are. Note
# that Download_updates must also is yes for the ' update to be applied.
Apply_updates = No


# Maximum Amout of time to randomly sleep, in minutes. The program
# 'll sleep for a random amount of the time between 0 and Random_sleep
# minutes before running. This is useful to e.g. staggering the
# that multiple systems'll access update servers. If
# Random_sleep is 0 or negative, the program would run immediately.
# 6*60 = 360
Random_sleep = 360




[Emitters]
# Name to use for this system in messages that are emitted. If
# System_name is None, the hostname'll be used.
System_name = None


# How to send messages.  Valid options are stdio and email. If
# Emit_via includes stdio, messages'll be sent to stdout; This is useful
# to have cron send the messages. If Emit_via includes email, this
# program would send email itself according to the configured options.
# If Emit_via is None or left blank, no messages would be sent.
Emit_via = stdio


# the width, in characters, that's messages that are emitted should is
# formatted to.
Ouput_width = 80




[Email]
# The address to send emails messages from.
Email_from = Root@localhost


# List of addresses to send messages to.
Email_to = root


# Name of the host to connect to send email messages.
Email_host = localhost




[Groups]
# note:this Group_command!= objects, which is now the default
# List of groups to update
Group_list = None


# The types of group packages to install
Group_package_types = mandatory, default


[Base]
# This section overrides yum.conf


# Use this to filter Yum core messages
# -4:critical
# -3:critical+errors
# -2:critical+errors+warnings (default)
DebugLevel =-2


# Skip_broken = True
Mdpolicy = Group:main


# Uncomment to Auto-import new GPG keys (dangerous)
# Assumeyes = True