linux training for beginners

Explain various raidRAID0:It's usually done with two plates.Write a file on two plates, respectively.This improves read and write speed.But it is not redundant and cannot be recovered by backup after data lossRAID1:It's done with two plates.That's what they call a mirror.Backup for each otherOnce a piece of data is lost, it can be recovered by another pieceRAID5:At least three plates requiredRAID5 is a compromise between RAID0 and RAID1.So it's 10/2=5.20170713l08-00 old boy

If the total capacity of the hard disk is greater than 2T, the system cannot be installed in MBR format.Use GPT formatYou can't use Fdisk to partition it at this time.To use parted to partitionMore than 2t hard disk partition, the old boy video used to 5 pieces of 600G hard diskThere are several ways to install the systemI only remember two of them.Method One: Take 2 pieces of RAID 1 for the remaining 3 pieces to do RAID5Method Two: All made RAID5, then the logical partition installation system2

The next section continues to say SersyncThis section is about the actual experiment of Sersync.Installation of primary server Sersync, settingAnd then a synchronous demo.Let people know more about the principle of synchronous automation softwareIn which the real-time synchronization is explainedWhen the amount of synchronization is highThe client may not be able to update in real time20170705l07-09-03 old boy Linux Operational

Tags: Linux basicsNote: By practicing, you can avoid adding more escape characters by using the-e option (that is, extending regular expressions) when using grep1Cp-r/etc/skel/home/tuser1 chmod-r 000/home/tuser12Vi/etc/group3vi/etc/passwd4Cp-r/etc/skel/home/hadoop chmod 700/home/hadoop5Chown-r hadoop:hadoop/home/hadoop/6Cat/proc//meminfo | grep "^[s,s]"Cat/proc//meminfo | Grep-e "^[s| S] "7.cat/etc/passwd | Grep-v "/sbin/nologin\>" | Cut-d:-f18.cat/

/wKiom1ed5UbwkvKjAAHU-XzUyaw119.png "title=" 7.png " alt= "Wkiom1ed5ubwkvkjaahu-xzuyaw119.png"/>650) this.width=650; "src=" Http://s1.51cto.com/wyfs02/M02/85/3D/wKioL1ed5XOQi1YMAAGWPqHx9Zk325.png "title=" 8.png " alt= "Wkiol1ed5xoqi1ymaagwpqhx9zk325.png"/>CP,RM,MV Differences in inode usageCP: Allocating idle inode numbersRM: When deleting data, the inode is deleted first and data is temporarily not deletedMV: On the same file system, the data does not move, just change the inodeWhen not on the

: Delete the user's home directory at the same time;Groupmod: Group Property ModificationGroupmod [OPTION] GROUPNAME-N group_name-G GIDGPASSWD: Set password for groupNEWGRP: Toggles the base group for the specified groupGroupdel: Deleting a groupChage: Modify the properties of user account and passwordchage [OPTION] ... LOGIN-D Last_day-E-L-M-M-WOther commands: CHFN, Chsh, Finger, WhoAmI, who, WFile permissions:There are three types of user access to files:R, W, XFile:R: You can use the file vie

Just one command, parted.Normal hard disk is more than 2T timeYou can't use Fdisk partitioning.This is the time to use tool parted to partition the rows.Hard disk larger than 2T to use GPT format cannot use MBR#parted/DEV/SDC mklable GPT#parted/DEV/SDC Mkpart Primary 0 200#parted/DEV/SDC Mkpart Primary 201 400#parted/DEV/SDC Mkpart Primary 401 1000#parted/DEV/SDC P ViewFormatting after partitioning is complete#mkfs. Ext3-b 4096/DEV/SDC1#mkfs. Ext3-b 4096/DEV/SDC2#mkfs. Ext3-b 4096/DEV/SDC3Mount

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with. D in the/etc directory to the/tmp/magedu.com directorymkdir/tmp/magedu.comCp-r/etc/*.d/tmp/magedu.com/ Description:-R recursion, which includes subdirectories.Also try some parameters, when the/tmp/magedu.com path does not exist, you need to first build this directory, and then copy.Exercise 3:1) Replace the lowercase letter in the/tmp/readme.test file with uppercase letters and write the results to the new file 1.txt tr [A-z] [a-z] (note that there are spaces between the two brackets)

It's mainly about rsync.On-Machine experimentand write some scripts.Here is the script for automatic backup#bak Site and logscd/var/html tar zcf/backup/www_$ (date +%f). tar.gz./wwwCd/app tar zcf/backup/logs_$ (date +%f). tar.gz./logs#bak SYS confCD/ tar zcf/backup/etc_$ (date +%f). tar.gz./scripts/bin/cp/var/spool/cron/root/backup/#rsync data to BakserverRsync-avzp/backup/rsync [Email protected]::backup/--password-file=/etc/Rsync.password#del data 7 days agoFind/backup-type f-name "*.tar.gz"-

Sersync pressure test in the next sectionThis section focuses on the pressure test text of the previous section to do a real stress testTest out exactly what the sersync pressure limit is.From 10 to 100 per second# Tree |wc-l #查看写了多少文件# uptime #查看负载Here is the test script#!/bin/shcount=100While TrueDoFor ((i=1;iDo/BIN/CP 10k.jpg/backup/test/$i/10k_echo $ (date) $RANDOM |md5sum |cut-c 1-8.jpgDoneSleep 1For ((i=1;iDo/BIN/CP 30k.jpg/backup/test/$i/10k_echo $ (date) $RANDOM |md5sum |cut-c 1-8.jpgDon