Skip to main content

Initial Settings : Services

 [1]. It's possible to display services' status like follows.

# the list of services that are active now

[root@dlp ~]# systemctl -t service

UNIT                            LOAD   ACTIVE SUB     DESCRIPTION

atd.service                     loaded active running Job spooling tools

auditd.service                  loaded active running Security Auditing Service

chronyd.service                 loaded active running NTP client/server

crond.service                   loaded active running Command Scheduler

dbus.service                    loaded active running D-Bus System Message Bus

.....

.....

user-runtime-dir@0.service      loaded active exited  /run/user/0 mount wrapper

user@0.service                  loaded active running User Manager for UID 0

vdo.service                     loaded active exited  VDO volume services


LOAD   = Reflects whether the unit definition was properly loaded.

ACTIVE = The high-level unit activation state, i.e. generalization of SUB.

SUB    = The low-level unit activation state, values depend on unit type.


45 loaded units listed. Pass --all to see loaded but inactive units, too.

To show all installed unit files use 'systemctl list-unit-files'.


# list of all services

[root@dlp ~]# systemctl list-unit-files -t service

UNIT FILE                                   STATE

arp-ethers.service                          disabled

atd.service                                 enabled

auditd.service                              enabled

autovt@.service                             enabled

blk-availability.service                    disabled

.....

.....

user-runtime-dir@.service                   static

user@.service                               static

vdo.service                                 enabled


181 unit files listed.

[2]. Stop and turn OFF auto-start setting for a service if you don'd need it. (it's smartd as an example below)

[root@dlp ~]# systemctl stop smartd

[root@dlp ~]# systemctl disable smartd

Comments

Post a Comment

Popular posts from this blog

C++ How to use Date and Time

The C++ standard library does not provide a proper date type. C++ inherits the structs and functions for date and time manipulation from C. To access date and time related functions and structures, you would need to include <ctime> header file in your C++ program. There are four time-related types: clock_t, time_t, size_t , and tm . The types clock_t, size_t and time_t are capable of representing the system time and date as some sort of integer. The structure type tm holds the date and time in the form of a C structure having the following elements: struct tm { int tm_sec ; // seconds of minutes from 0 to 61 int tm_min ; // minutes of hour from 0 to 59 int tm_hour ; // hours of day from 0 to 24 int tm_mday ; // day of month from 1 to 31 int tm_mon ; // month of year from 0 to 11 int tm_year ; // year since 1900 int tm_wday ; // days since sunday int tm_yday ; // days since January 1st int tm_isdst ; // hours of daylight savin...
Post a Comment
Read more

C++ References

A reference variable is an alias, that is, another name for an already existing variable. Once a reference is initialized with a variable, either the variable name or the reference name may be used to refer to the variable. C++ References vs Pointers: References are often confused with pointers but three major differences between references and pointers are: You cannot have NULL references. You must always be able to assume that a reference is connected to a legitimate piece of storage. Once a reference is initialized to an object, it cannot be changed to refer to another object. Pointers can be pointed to another object at any time. A reference must be initialized when it is created. Pointers can be initialized at any time. Creating References in C++: Think of a variable name as a label attached to the variable's location in memory. You can then think of a reference as a second label attached to that memory location. Therefore, you can access the contents of the variabl...
Post a Comment
Read more

Lambda Function with Amazon SNS

  Amazon SNS is a service used for push notification. In this chapter, we will explain working of AWS Lambda and Amazon SNS with the help of an example where will perform the following actions − Create Topic in SNS Service and use AWS Lambda Add Topics to CloudWatch Send SNS text message on phone number given. Requisites To create Topic in SNS Service and use AWS Lambda Add Topics to CloudWatch, we need not follow the steps given below − Create Topic in SNS Create Role for permission in IAM Create AWS Lambda Function Publish to topic to activate trigger Check the message details in CloudWatch service. To send SNS text message on phone number given, we need to do the following − Add code in AWS Lambda to send message to your phone. Example In this example, we will create a topic in SNS. When details are entered in the topic to publish, AWS Lambda is triggered. The topic details are logged in CloudWatch and a message is sent on phone by AWS Lambda. Here is a basic block diagram which...
Post a Comment
Read more