Shulou(Shulou.com)06/02 Report--

In this issue, the editor will bring you what are the problems and orders encountered by CDH-cloudera-manager. The article is rich in content and analyzes and narrates it from a professional point of view. I hope you can get something after reading this article.

Write down some of the problems and commands encountered at work:

1.Host Monitor is not running. This error is very common, usually what service is not started. In most cases, it would be nice to restart. If there are any problems, check the configuration or even reinstall CDH.

two。 Modify the slave ip address of the host.

CDH has no command to modify the ip address, so you have to manually modify the configuration yourself.

1) stop the cloudera-manager-sever service and stop all cloudera-manager-agent services.

Linux command: systemctl stop cloudera-scm-server

Systemctl stop cloudera-scm-agent

2) modify the setting of the ip address in the database, if you do not set up the database yourself when installing CDH, then the default database is postgresql, and if you set it, the information exists in the database of your choice. I chose mysql. First, look at the login password of mysql:

Linux command: grep password / etc/cloudera-scm-server/db.properties

If you are interested, you can take a look at this file, which contains the database ip address, database type, database password, database name and user for storing cdh.

Once you know the database password, you can log in to the database and modify the ip. You can modify it either through the shell command line or through a graphical interface, as long as you change it. The default database is scm. Find the HOSTS table in it and modify the IP_ADDRESS field inside.

Linux command, log in to mysql: mysql-u root-p

I am logged in as a root user mysql, the specification should be logged in as a scm user, that is, change the above root to scm. -u represents the user, and-p represents the password, separated by a space.

After that, you will be asked to enter your password and log in to the database.

Mysql command: show databases

The mysql command usually ends with ";" to see which databases are available, and the result is shown below:

There are two databases, and then switch to the scm database to see which tables are available:

Mysql command: use scm

Show tables

As shown below:

An error will be reported if the database is not specified to use show tables; directly, and after you specify it, you can see which tables there are. We need to modify the data in the HOSTS table to see what data is in it.

Mysql command: select * from HOSTS

You can see that these contents are not arranged neatly on the shell command line, but if you look at the field names, you can see that what needs to be modified is IP_ADDRESS.

Mysql command: update scm.`HOSTS` set `NAME` = 'nodeN',IP_ADDRESS='xxx.xxx.xxx.xxx' where `HOST_ ID` =' num'

Modify the ip address and hostname that need to be modified, and then see if there is any problem with the modified database. If there is no problem, exit mysql and modify the clouderaManager configuration file.

Mysql command: quit

3) there are two kinds of files to be modified, one is CM file modification, the other is Agent file modification.

Linux directive:

# CM file

Vi / etc/cloudera-scm-server/db.properties

Com.cloudera.cmf.db.host= new CM hostname

# Agent file

Vi / etc/cloudera-scm-agent/config.ini

Server_host = new host ip

After modifying all the configuration files, start cloudera-scm-server first, and then start cloudera-scm-agent.

Linux command:

Systemctl start cloudera-scm-server

Systemctl start cloudera-scm-agent

So that the ip address can be read correctly. If there are any more questions, it is recommended to restart.

3. Monitor the running log of CM

Linux command: tail-f / var/log/cloudera-scm-server/cloudera-scm-server.log

Tail-f / var/log/cloudera-scm-agent/cloudera-scm-agent.log

4.clouderaManager web interface address

The default port of ClouderaManager is 7180 hadoop. The default port of HDFS is 50070 after hadoop3.0, and 9870 after HDFS. Check your own HDFS version when 50070 cannot access the page.

Linux command to view hadoop version: hadoop version

Insufficient permissions to display the / tmp file in 5.hdfs. Error message: Permission denied: user=dr.who, access=READ_EXECUTE, inode= "/ tmp": root:supergroup:drwx-wx-wx

To modify the / tmp file permissions under the hdfs user.

Linux command: hdfs dfs-chmod-R 755 / tmp

These are the problems and commands that the editor shares with you on CDH-cloudera-manager. If you happen to have similar doubts, you might as well refer to the above analysis to understand. If you want to know more about it, you are welcome to follow the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.