1 Android Simulation graphic problems

Problems:

- Device display problems

- Device run slow and crash.

Solution:

Change Emulate graphic from Automatic to another graphic.

-  Devices > Click ... icon > Show on Disk > config.ini and edit:
hw.gpu.enabled=yes
hw.gpu.mode=software

 

How to install WordPress in CentOS and config NO-IP for your website

 

1. How to install firebase CLI in windows

Ref: https://firebase.google.com/docs/hosting/quickstart

Windows:
$ npm -g install firebase-tools
$ firebase --version
$ firebase login
$ firebase use --add (select your project id)

2. Run Firebase project in local
$ firebase serve --only hosting // run local only
$ firebase serve --host 0.0.0.0 // allow access any source

 

Docker

===========

===========

1. Download images to local

$ docker pull <image_name:tag>

Docker hub: https://hub.docker.com/ 

2. Run a images
$ docker run -name <unique_container_name>  ...
$ docker run --help

3. List container

$ docker ps -a ///list all
$ docker ps //list container is running

4. Start/Stop Container

$ docker stop <container_id/container_name>
$ docker start <container_id/container_name>

5. Remove container/images

$ docker rm <container_id/container_name>
$ docker rmi <img_name>

6. Check container detail

$docker inspect <container_id/container_name>

7.  Install docker-compose

Ref: https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-compose-on-centos-7

//Check docker-compose version before install. In there docker-compose version is 1.23.2. 
// Check latest docker-compose here: 

$ sudo curl -L "https://github.com/docker/compose/releases/download/1.23.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

$ sudo chmod +x /usr/local/bin/docker-compose
$ docker-compose --version

Remove docker-compose
#by curl
$ sudo rm /usr/local/bin/docker-compose

#by yum, apt-get

$ sudo apt-get remove docker-compose
$ sudo yum remove docker-compose

#by pip
$ pip uninstall docker-compose

=======================

Create Volume

$ docker volume create <volume_name>

=======================

DOCKER Compose

Docker Compose is a tool for defining and running multi-container Docker applications.

 Instead of managing each container individually with long docker run commands, you describe your entire application stack in a single YAML file (docker-compose.yml), then spin everything up with one command.

A simple example docker-compose.yml:

services:

  web:

    image: nginx

    ports:

      - "80:80"

  db:

    image: postgres

    environment:

      POSTGRES_PASSWORD: secret

  cache:

    image: redis

Key things it handles for you:

Networking — services can reach each other by name (e.g., your app can connect to db:5432)

Environment variables — easily inject config per service

Volumes — persist or share data between containers and your host

Build — can build images from a Dockerfile as part of the process

Dependencies — depends_on lets you control startup order

Command	What it does
docker compose up	Start all services
docker compose up -d	Start in background (detached)
docker compose down	Stop and remove containers
docker compose logs	View output from services
docker compose ps	List running services

=======================

Stop all docker container

$ docker stop $(docker ps -q)

Remove all container

$ docker rm $(docker ps -aq)

Remove all image on container

$ docker rmi $(docker images -q)

Problems:

1. Warning: Stop docker.service, but it can still be activated by : docker.socker

Solution:

$ systemctl stop docker.socket

2. Access maridb via docker

$ docker exec -it mariadb10.4 bash // access docker container.

$mysql -u root -p

is updating....

 

Ref:

1. https://woocommerce.com/document/woocommerce-rest-api/
2. https://woocommerce.github.io/woocommerce-rest-api-docs/wp-api-v2.html?php#list-all-products

Case study: There are a way used show Product in Mobile App. We can easy manage product without writing backend system.

 

I. Không thể Zoom Tài Liệu

Nguyên nhân: Bạn đang dùng chế độ view Side By Side

Cách khắc phục:

Menu > View > Chọn Vertical

II. Cách đánh số thứ tự cho từng trang trong word

Cách 1: Đánh số thứ tự cho toàn bộ văn bản

- Chọn Insert > Page Number

Top of page: Chèn phía trên trang

Bottom of page: Chèn phía dưới trang

- Click vào là chọn nơi bạn cần đánh dấu

Cách 2: Đánh số trang cho vị trí bất kì

- Để dánh số trang bất kì, bạn cần chia word thành nhiều Section khác nhau để đánh số. Ví dụ bạn muốn đánh dấu trang số 2 từ 1 đến cuối trang, trang bìa thì bạn bỏ không đánh dấu.

- Bạn chia trang bìa là section 1, và trang thứ 2 trở đi là section 2.

Bạn làm như sau:

- Trỏ chuột vào trang thứ 2 hoặc bất kì trang nào bạn muốn để bắt đầu section #2.

- Bạn vào Layout > Break > Continous

- Lúc này tài liệu bạn đã chia thành 2 section.

- Vào Insert > Page Number > Format Page Number > Chọn Start at: 1

- Sau đó bạn vào trang bìa > Double Click vào Footer > xóa số tự của trang đi.

 

I. Install Oracle DB 21c In CentOS 8

Ref:
1. Oracle 21c : https://www.oracle.com/database/technologies/oracle21c-windows-downloads.html
2. CentOS v8 : https://www.centos.org/download/

3. Video installation: https://www.youtube.com/watch?v=8rEAf2hPv60

4. Installation: https://unixcop.com/how-to-install-oracle-database-21c-on-centos-8/

Step 1: Set hostname

$hostnamectl set-hostname oracle.unixcop.local

Step 2: Install Oracle Database preinstall packages.

$dnf install oracle-database-preinstall-21c -y

# If above is cannot install, download rpm in url: 
# https://yum.oracle.com/repo/OracleLinux/OL8/appstream/x86_64/index.html
$dnf localinstall oracle-database-preinstall-21c-1.0-1.el8.x86_64.rpm

Step 3: Update packages.

$ dnf update -y

Step 4: Create the user

$ useradd oracle
$ passwd oracle

Step 5: Disabled SELinux

$ cat /etc/selinux/config
$ vi /etc/selinux/config

Step 6: Disable Firewall

$ systemctl status firewalld
$ systemctl disable firewalld

Step 7: Make environments

$ mkdir -p /u01/app/oracle
$ mkdir -p /u01/app/oracle/product/21.0.0/dbhome_1
$ mkdir -p /u01/app/oraInventory
$ mkdir -p /u02/oradata
$ chown -R oracle:oinstall /u01 /u02
$ chown -R oracle:oinstall /u01/app/oraInventory
$ chmod -R 775 /u01 /u02
$ mkdir /home/oracle/scripts
$ cat > /home/oracle/scripts/setEnv.sh <<EOF
> # Oracle Settings
> export TMP=/tmp
> export TMPDIR=\$TMP
>
> export ORACLE_HOSTNAME=oracle.unixcop.local
> export ORACLE_UNQNAME=cdb1
> export ORACLE_BASE=/u01/app/oracle
> export ORACLE_HOME=\$ORACLE_BASE/product/21.0.0/dbhome_1
> export ORA_INVENTORY=/u01/app/oraInventory
> export ORACLE_SID=cdb1
> export PBD_NAME=pdb1
> export DATA_DIR=/u02/oradata
>
> export PATH=/usr/sbin:/usr/local/bin:\$PATH
> export PATH=\$ORACLE_HOME/bin:\$PATH
>
> export LB_LIBRRARY_PATH=\$ORACLE_HOME/lib:/lib:/usr/lib
> export CLASSPATH=\$ORACLE_HOME/jlib:\$ORACLE_HOME/rdbms/jlib
> EOF

$ echo ". /home/oracle/scripts/setEnv.sh" >> /home/oracle/.bash_profile

Step 8: Create start/stop oracle db:

$ cat > /home/oracle/scripts/start_all.sh <<EOF
> #!/bin/bash
> . /home/oracle/scripts/setEnv.sh
>
> export ORAENV_ASK=NO
> . oraenv
> export ORAENV_ASK=YES
>
> dbstart \$ORACLE_HOME
> EOF

$ cat > /home/oracle/scripts/stop_all.sh <<EOF
> #!/bin/bash
> . /home/oracle/scripts/setEnv.sh
>
> export ORAENV_ASK=NO
> . oraenv
> export ORAENV_ASK=YES
>
> dbshut \$ORACLE_HOME
> EOF
$ chown -R oracle:oinstall /home/oracle/scripts
$ chmod u+x /home/oracle/scripts/*.sh

Step 9: Upload unzip Oracle DB installter to server follow the path:

/u01/app/oracle/product/21.0.0/dbhome_1

$ ./runInstaller

Note: Switch to user "oracle" in GUI and run this scripts.

* Running RPM packages to Install Oracle Database:

Ref:  https://docs.oracle.com/en/database/oracle/oracle-database/21/ladbi/running-rpm-packages-to-install-oracle-database.html#GUID-BB7C11E3-D385-4A2F-9EAF-75F4F0AACF02

 

1. Access console of Aruba

Step 1: Open putty

Step 2: Type IP of Aruba 

Step 3: Enter Admin/Password of Admin (same on GUI Login)

2. CLI Command line

Ref: https://www.arubanetworks.com/techdocs/Instant_84_WebHelp/Content/instant-cli/clock-set.htm?Highlight=clock%20set

# show clock
$show clock

#set clock
$ clock set yyyy mm dd hh mm ss

#set NTP server
$ config  (go to config mode )
$ ntp-server <hostname>
$ end (exit config mode)
$commit apply  (apply config)

#check NTP status|
$ show ntp status

#Show NTP debug
$ show ntp debug

#Show time-range
$ show time-range

3. Turn off Broadcast filtering

If all clients cannot broadcast together, we can turn off that:

1. Network > Select Network > Advance Setting > Broadcase filtering : Disable

4. Resolve NTP Time Not Sync in Mikrotik

Description:

In some areas, the home network infrastructure is still limited, applying policies to each of their Internet users, especially in rural areas and remote areas. Many places block/change NTP ports, specifically UDP port 123.

At that time, your Mikrotik Router will not be able to update and synchronize the time, no matter which NTP Server you set, the status is still in the waiting state as shown above, detecting other unexpected errors. Maybe at this time you think that the Mikrotik device is faulty, you will update, downgrade the firmware for the device, even Re-Install RouterOS for the device but still cannot solve the problem.

Ip > Firewall :

 

Run Java App as a Service in Cent OS

References:

1. https://dzone.com/articles/run-your-java-application-as-a-service-on-ubuntu

Step 1: Create user

• You should create a user for your service.

Ex:

$ groupadd group1

$ useradd user1 -M -s /bin/nologin -g gtest

Step 2: Create a service

$ vi /etc/systemd/system/your-service.service

Copy/past:

#!/bin/bash

[Unit]

Description=VCS Netty Service

[Service]

User=user1

# The configuration file application.properties should be here:

#change this to your workspace

WorkingDirectory=/home/user1

#path to executable.

#executable is a bash script which calls jar file

ExecStart=/home/user1/run-service

SuccessExitStatus=143

TimeoutStopSec=10

Restart=on-failure

RestartSec=5

[Install]

WantedBy=multi-user.target

Step 3: Create a Bash Script to Call Your Service

$ cd /home/user1

$ vi run-service.sh

#!/usr/bin/bash

/usr/bin/java -jar NETTY_SERVER-0.0.1-SNAPSHOT.jar

$ chmod u+x run-service.sh

Step 4: Start the Service

$ systemctl daemon-reload

$ systemctl enable your-service.service

$ systemctl start your-service

$ systemctl status your-service

Step 4: Check log

$ journalctl -f -u your-service

 

REACT NATIVE - REALM DATABASE

Ref:
1. https://docs.mongodb.com/realm-legacy/docs/javascript/latest.html#examples
2. To do list example: https://hellokoding.com/todo-app-with-react-native-realm/

1. Open Realms

//Schema
const PersonSchema = {
  name: 'Person',
  properties: {
    realName:    'string', // required property
    displayName: 'string?', // optional property
    birthday:    {type: 'date', optional: true}, // optional property
  }
};
// Get the default Realm with support for our objects
Realm.open({schema: [Car, Person]})
  .then(realm => {
    // ...use the realm instance here
  })
  .catch(error => {
    // Handle the error here if something went wrong
  });
// Open a realm at another path
Realm.open({
  path: 'anotherRealm.realm',
  schema: [CarSchema]
}).then(/* ... */);

2. Get the current schema version

// Update to to the new schema
Realm.open({schema: [UpdatedPersonSchema], schemaVersion: 1});
//Get current version
const currentVersion = Realm.schemaVersion(Realm.defaultPath);

2. List of properties

realm.write(() => {
  let charlie = realm.create('Person', {
    name: 'Charlie',
    testScores: [100.0]
  });

  // Charlie had an excused absense for the second test and was allowed to skip it
  charlie.testScores.push(null);

  // And then he didn't do so well on the third test
  charlie.testScores.push(70.0);
});

3. Relationship
* To-One Relationship

const PersonSchema = {
  name: 'Person',
  properties: {
    // The following property definitions are equivalent
    car: {type: 'Car'},
    van: 'Car',
  }
};

realm.write(() => {
  const nameString = person.car.name;
  person.car.miles = 1100;

  // create a new Car by setting the property to an object
  // with all of the required fields
  person.van = {make: 'Ford', model: 'Transit'};

  // set both properties to the same car instance
  person.car = person.van;
});

* To-Many Relationships

const PersonSchema = {
  name: 'Person',
  properties: {
    // The following property definitions are equivalent
    cars: {type: 'list', objectType: 'Car'},
    vans: 'Car[]'
  }
}

let carList = person.cars;

// Add new cars to the list
realm.write(() => {
  carList.push({make: 'Honda', model: 'Accord', miles: 100});
  carList.push({make: 'Toyota', model: 'Prius', miles: 200});
});

let secondCar = carList[1].model;  // access using an array index

4. Query

* Get max value in Collection List.
For example: you want to get max of id Person in List. you can do like that

const personList = realm ? realm.objects('Personal') : null;

let idIdx = 0;
if (personList != null && personList.length != 0) {
   idIdx = personList.max('id');
   idIdx++;
}

* Passed para to query
Each subsequent argument is used by the placeholders (e.g. $0, $1, $2, …) in the query.

let person = personList.filtered('id=$0', id);

is updating