inodes and soft and hard links

Article directory: 1. Understand the file system 1.1 What is an inode 1.2 Disk Understanding 1.2.1 The hardware structure of the disk 1.2.2 Disk partitioning 1.2.3 EXT2 file system Two, soft and hard links 2.1 Soft link 2.2 Hard link 1. Understanding the file system 1.1 What is an inode Inodes are data structures in […]

Inode and logical blocks, directory structure, and implementation of mounting Source level analysis of the file system structure of the linux kernel

bitmap.c bitmap related Encapsulates macros for operating bitmaps such as set_bit clear_bit find_first_zero clear_block Corresponding to i-node bitmap and logical block bitmap, there are four corresponding functions free_inode, new_inode, free_block, new_block new_block creates a logical block Find the logical block bitmap through super_block, set the first free bit (find_first_zero) of the logical block bitmap to […]

[Solved] hadoop problem solving Permission denied: user=root, access=READ_EXECUTE, inode=”

Solution: Add a personal account in /etc/profile or ~/.bashrc (try both, whichever works) Enter settings file vim /etc/profile or vim ~/.bashrc Add configuration export HADOOP_USER_NAME=[Personal Account] Effective source /etc/profile or source ~/.bashrc Get it! Supplemental hadoop tips In the above two configuration files, simplify your hadoop commands alias hrm=’hadoop fs -rm -r’ alias hmkdir=’hadoop fs […]

[Solved] Hadoop common errors and solutions, Permission denied: user=dr.who, access=WRITE, inode=”/”:summer:supergroup:drwxr-xr-x

Article table of contents 4. Common errors and solutions 1) The firewall is not closed, or YARN is not started 7) Does not recognize hostnames 8) DataNode and NameNode processes can only work one at a time. 9) The execution command does not take effect. When pasting the command in Word, there is no distinction […]

[Solved] Permission denied: user=dr.who, access=WRITE, inode=”/output”:root:supergroup:drwxr-xr-x

1. Problem description: When viewing the hdfs front-end page in hadoop, an error is reported when deleting a folder or document, Permission denied: user=dr.who, access=WRITE, inode=”/ output”:root:supergroup:drwxr-xr-x. 2. Reason: Because the current user lacks relevant permissions. 3. Solution: Enter the /hadoop-3.1.3/etc/hadoop directory, use the vim command to edit the core-site.xml file, and add the following […]

[Solved] Java uploading files to hdfs reports an error: Permission denied: user=17215, access=WRITE, inode=“/“:hadoop:supergroup:drwxr-xr-x

Question: Reason The Windows system connects to the Linux Hadoop file system, for the problem of no permissions Solution The first type: (you can test it yourself) After adding the following configuration file to hdfs-site.xml, restart the hadoop file system <property> <name>dfs.permissions</name> <value>false</value> </property> Second: In the main method of the program, add to the […]