10.32/10.33 rsync synchronizes 10.34 Linux system logs via service Screen tool

How to use Background services

Establish an rsync server on the remote host, configure the various applications of rsync on the server, and then connect the machine to a remote rsync server as a client of rsync.

Set up and configure Rsync profile/etc/rsyncd.conf on the 128 host to edit your rsyncd.conf to the following:

[Email protected] ~]# vim/etc/rsyncd.conf#/etc/rsyncd:configuration file for rsync daemon Modeport=873log File=/var/lo G/rsync.logpid file=/var/run/rsyncd.pidaddress=192.168.193.128# See rsyncd.conf Mans page for more options.# Configuration Example:[test]path=/root/rsyncread only=nolist=trueuid = Rootgid = RootUse Chroot=truemax connections= 4auth users=testsecrets file=/etc/rsyncd.passwdhosts allow=192.168.193.128

The Port,logfile,pid file,address in rscond.com is the global configuration, and the following part of [test] is the module configuration. Man rsyncd.conf can get more information.

Port: Specify on which port to start the RSYNCD service, which is port 873 by default.

Log file: Specifies the log files.

PID file: Specify the PID files, the role of this file involves the start of services, stop and other process management operations.

Address: Specifies the IP to start the RSYNCD service.

[]: Specifies the module name.

Path: Specifies the path where the data is stored.

Use Chroot True|false: Represents the first chroot to the directory specified by the path parameter before transferring the file.

Max connections: Specifies the maximum number of connections, which defaults to 0, which means there is no limit.

Read Only Ture|false: If true, you cannot upload to the path specified by the module.

List: Indicates whether the module is listed when the user queries the available modules on the server, set to True to be listed, and set to False to hide.

Uid/gid: Specifies which user/group is transferred as the file is transferred.

Auth Users: Specifies the user name to use when transferring.

Secrets file: Specifies the password files.

Hosts allow: Represents a host that is allowed to connect to the module.

Edit Secrets file and give 600 permissions after saving.

[[email protected] etc]# cat/etc/rsyncd.passwd[[email protected] etc]# vim/etc/rsyncd.passwd[[email protected] etc]# CA T/etc/rsyncd.passwdtest:test123[[email protected] etc]# chmod 600/etc/reyncd.passwdchmod: Cannot Access "/ETC/REYNCD.PASSWD": No file or directory [[email protected] etc]# chmod 600/etc/rsyncd.passwd

Linux system logs

/var/log/messages

The boot information at the start of the system will be stored in this file in the other state of the runtime.

It is implemented by the Logrotate tool, and its configuration file is/etc/logrotate.conf.

[[email protected] ~]# cat /etc/logrotate.conf# see  "Man logrotate"   For details# rotate log files weeklyweekly# keep 4 weeks worth  of backlogsrotate 4# create new  (empty)  log files after  rotating old onescreate# use date as a suffix of the rotated  filedateext# uncomment this if you want your log files  compressed#compress# rpm packages drop log rotation information into  This directoryinclude /etc/logrotate.d# no packages own wtmp and btmp  -- we ' ll rotate them here/var/log/wtmp {    monthly     create 0664 root utmp        minsize  1m    rotate 1}/var/log/btmp {    missingok    monthly     create 0600 root utmp    rotate 1}#  System-specific logs may be also be configured here.

Man rsyslog.com See more information.

Dmesg

can display the system boot information

[[Email protected] ~]# dmesg |head[    0.000000] initializing  cgroup subsys cpuset[    0.000000] Initializing cgroup  subsys cpu[    0.000000] initializing cgroup subsys cpuacct[     0.000000] Linux version 3.10.0-862.el7.x86_64  ([email  Protected])   (gcc version 4.8.5 20150623  (red hat 4.8.5-28)   (GCC)   )   #1  smp fri apr 20 16:44:24 utc 2018[    0.000000 ] command line: boot_image=/vmlinuz-3.10.0-862.el7.x86_64 root=uuid= 23c138ca-3a70-447e-9028-e002f1d0dea9 ro crashkernel=auto rhgb quiet. utf-8[    0.000000] disabled fast string operations[     0.000000] e820: BIOS-provided physical RAM MAP:[    0.000000] BIOS-E820: [MEM 0X0000000000000000-0X000000000009EBFF]  usable[    0.000000] BIOS-e820: [mem  0x000000000009ec00-0x000000000009ffff] reserved[    0.000000] bios-e820: [ Mem 0x00000000000dc000-0x00000000000fffff] reserved

Security Log

[[email protected] ~]# last |headroot     pts/1         192.168.193.1    Fri Jul 20 09:08    still logged inroot     pts/0         192.168.193.1    Thu Jul 19 14:32   still  logged inroot     pts/0         192.168.193.1    thu jul 19 08:58 - 14:31   (05:32) root      pts/0        192.168.193.1     Wed Jul 18 15:46 - 21:24   (05:37) root      pts/0        192.168.193.1    tue jul  17 11:11 - 18:21   (07:09) root     pts/1         192.168.193.1    Mon Jul 16 18:49 - 20:41   (01:52 ) root     pts/0        192.168.193.1     Mon Jul 16 18:44 - 18:49   (00:04) root      pts/0        192.168.193.1    mon  Jul 16 18:37 - 18:43   (00:06) root     pts/1         192.168.193.1    mon jul 16 18:16  - 18:37   (00:21) root     tty1                            mon jul&Nbsp;16 18:14   still logged in 

Xargs applications

Find files with the current directory creation time greater than 10 days, and then delete them.

[[email protected] ~]# find. Mtime +10 |xargs RM

[[email protected] ~]# mkdir test[[email protected] ~]# CD Test[[email protected] test]# touch 1.txt 2.txt 3.txt 4.txt 5.t Xt[[email protected] test]# ls1.txt 2.txt 3.txt 4.txt 5.txt[[email protected] test]# ls *.txt |xargs-n1-i{} mv {} {} _bak[[email protected] test]# ls1.txt_bak 2.txt_bak 3.txt_bak 4.txt_bak 5.txt_bak

Screen Tool Introduction

Using Nohup

First write a sleep.sh script, put it in the background to execute.

[Email protected] test]# cat/usr/local/sbin/sleep.sh! /bin/bash[[email protected] test]# nohup sh/usr/local/sbin/sleep.sh &[1] 40760

Screen tool

Screen is a window manager that can multiplex a physical terminal across multiple processes.

Install the screen command Yum install-y screen

-bash-4.2# Screen-lsthere is a screen on:40865.pts-1.aminglinux-123 (Detached) 1 Socket in/var/run/screen/s- Root.

10.32/10.33 rsync synchronizes 10.34 Linux system logs via service Screen tool