一、REHL8 WEB控制台管理系统

登录一台服务器有哪些方法：

本地登录、VNC、XSHELL、web控制台登录

1.1 什么是web控制台

web控制台是一个基于web的红帽企业版Linux8界面，用于管理和监控本地系统及位于网络环境中的linux服务器

RHEL的web控制台是交互式服务器管理界面，可以直接通过浏览器与真实的linux操作系统进行直接交互。

1.2 web控制台可以做什么

（1）监控基本系统功能，例如硬件信息，时间配置，性能配置等

（2）检查系统日志文件

（3）管理网络接口和配置防火墙

（4）管理虚拟机

（5）管理用户帐户

（6）监视和配置系统服务

（7）管理软件包

（8）配置SELinux

（9）更新软件

（10）访问终端

1.3 操作步骤

服务器开机，有网络，可以连接公网

先检查自己的服务器是否默认安装了这个服务 cockpit

[root@wentan ~]# yum list | grep cockpit
#RHEL8 默认已经安装了cocpit这个服务
cockpit.x86_64                                         185-2.el8                                              @anaconda 
cockpit-bridge.x86_64                                  185-2.el8                                              @anaconda 
cockpit-packagekit.noarch                              184.1-1.el8                                            @AppStream
cockpit-storaged.noarch                                184.1-1.el8                                            @AppStream
cockpit-system.noarch                                  185-2.el8                                              @anaconda 
cockpit-ws.x86_64                                      185-2.el8                                              @anaconda 
subscription-manager-cockpit.noarch                    1.23.8-35.el8                                          @anaconda 
cockpit.x86_64                                         251.1-1.el8                                            base      
cockpit-bridge.x86_64                                  251.1-1.el8                                            base      
cockpit-composer.noarch                                31.1-1.el8                                             AppStream 
cockpit-doc.noarch                                     251.1-1.el8                                            base      
cockpit-machines.noarch                                251.1-1.el8                                            AppStream 
cockpit-packagekit.noarch                              251.1-1.el8                                            AppStream 
cockpit-pcp.x86_64                                     251.1-1.el8                                            AppStream 
cockpit-podman.noarch                                  33-1.module_el8.5.0+890+6b136101                       AppStream 
cockpit-session-recording.noarch                       7-2.el8                                                AppStream 
cockpit-storaged.noarch                                251.1-1.el8                                            AppStream 
cockpit-system.noarch                                  251.1-1.el8                                            base      
cockpit-ws.x86_64                                      251.1-1.el8                                            base      
subscription-manager-cockpit.noarch                    1.28.21-3.el8                                          base      
#检查cockpit是否开机自动启动，发现cockpit.socket 是disable状态
[root@wentan ~]# systemctl list-unit-files | grep cockpit
cockpit-motd.service                        static   
cockpit.service                             static   
cockpit.socket                              disabled 

#启动cockpit这个服务
[root@wentan ~]# systemctl start cockpit.socket 
[root@wentan ~]# systemctl enable cockpit.socket 
Created symlink /etc/systemd/system/sockets.target.wants/cockpit.socket → /usr/lib/systemd/system/cockpit.socket.

#启动cockpit.service服务
[root@wentan ~]# systemctl start cockpit.service 
[root@wentan ~]# systemctl status cockpit.service 
● cockpit.service - Cockpit Web Service
   Loaded: loaded (/usr/lib/systemd/system/cockpit.service; static; vendor preset:>
   Active: active (running) since Wed 2022-01-19 10:41:40 CST; 17s ago
     Docs: man:cockpit-ws(8)
  Process: 8226 ExecStartPre=/usr/sbin/remotectl certificate --ensure --user=root >
 Main PID: 8230 (cockpit-ws)
    Tasks: 2 (limit: 23861)
   Memory: 2.8M
   CGroup: /system.slice/cockpit.service
           └─8230 /usr/libexec/cockpit-ws

防火墙策略：

可以关闭系统防火墙或者选择防火墙放行

RHEL8系统默认已经放行了cockpit服务

firewall-cmd --add-service=cockpit --permanent
firewall-cmd --reload #重载以生效这个规则

最后RHEL系统的web控制台的地址为服务器ip地址的9090端口

192.168.253.128:9090 (服务器地址)

输入用户密码登录

二、日志系统 RSYSLOG

使用了日志消息类型和优先级来确定到底如何处理

日志系统的配置文件： /etc/rsyslog.conf

2.1 日志消息的类型：

2.2 日志消息的优先级

从高到低 8个标准

2.3 日志信息里的内容

（1）会记录日志发生的时间

（2）发送该日志消息的主机

（3）发送该日志消息的程序，哪个PID

（4）日志消息的主内容

三、ISCSI 实验

首先需要两台虚拟机，恢复初始化状态

一台命名为SAN-server 一台命名为SAN-client

安装yum 源，关闭防火墙，同时ISCSI需要额外安装一块硬盘

3.1 服务端配置

#服务端
[root@wentan ~]# hostnamectl set-hostname SAN-server
[root@wentan ~]# bash
#接下来需要安装ISCSI的工具
[root@SAN-server ~]# yum install -y targetcli
[root@SAN-server ~]# systemctl enable target
Created symlink /etc/systemd/system/multi-user.target.wants/target.service → /usr/lib/systemd/system/target.service.
[root@SAN-server ~]# systemctl start target

#分区选择一块共享给SAN客户
[root@SAN-server ~]# fdisk /dev/nvme0n2

Welcome to fdisk (util-linux 2.32.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0x31fc34c5.

Command (m for help): n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-41943039, default 2048): 
Last sector, +sectors or +size{K,M,G,T,P} (2048-41943039, default 41943039): +10G

Created a new partition 1 of type 'Linux' and of size 10 GiB.

Command (m for help): p
Disk /dev/nvme0n2: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x31fc34c5

Device         Boot Start      End  Sectors Size Id Type
/dev/nvme0n2p1       2048 20973567 20971520  10G 83 Linux

Command (m for help): m

Help:

  DOS (MBR)
   a   toggle a bootable flag
   b   edit nested BSD disklabel
   c   toggle the dos compatibility flag

  Generic
   d   delete a partition
   F   list free unpartitioned space
   l   list known partition types
   n   add a new partition
   p   print the partition table
   t   change a partition type
   v   verify the partition table
   i   print information about a partition

  Misc
   m   print this menu
   u   change display/entry units
   x   extra functionality (experts only)

  Script
   I   load disk layout from sfdisk script file
   O   dump disk layout to sfdisk script file

  Save & Exit
   w   write table to disk and exit
   q   quit without saving changes

  Create a new label
   g   create a new empty GPT partition table
   G   create a new empty SGI (IRIX) partition table
   o   create a new empty DOS partition table
   s   create a new empty Sun partition table

Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): l

 0  Empty           24  NEC DOS         81  Minix / old Lin bf  Solaris        
 1  FAT12           27  Hidden NTFS Win 82  Linux swap / So c1  DRDOS/sec (FAT-
 2  XENIX root      39  Plan 9          83  Linux           c4  DRDOS/sec (FAT-
 3  XENIX usr       3c  PartitionMagic  84  OS/2 hidden or  c6  DRDOS/sec (FAT-
 4  FAT16 <32M      40  Venix 80286     85  Linux extended  c7  Syrinx         
 5  Extended        41  PPC PReP Boot   86  NTFS volume set da  Non-FS data    
 6  FAT16           42  SFS             87  NTFS volume set db  CP/M / CTOS / .
 7  HPFS/NTFS/exFAT 4d  QNX4.x          88  Linux plaintext de  Dell Utility   
 8  AIX             4e  QNX4.x 2nd part 8e  Linux LVM       df  BootIt         
 9  AIX bootable    4f  QNX4.x 3rd part 93  Amoeba          e1  DOS access     
 a  OS/2 Boot Manag 50  OnTrack DM      94  Amoeba BBT      e3  DOS R/O        
 b  W95 FAT32       51  OnTrack DM6 Aux 9f  BSD/OS          e4  SpeedStor      
 c  W95 FAT32 (LBA) 52  CP/M            a0  IBM Thinkpad hi ea  Rufus alignment
 e  W95 FAT16 (LBA) 53  OnTrack DM6 Aux a5  FreeBSD         eb  BeOS fs        
 f  W95 Ext'd (LBA) 54  OnTrackDM6      a6  OpenBSD         ee  GPT            
10  OPUS            55  EZ-Drive        a7  NeXTSTEP        ef  EFI (FAT-12/16/
11  Hidden FAT12    56  Golden Bow      a8  Darwin UFS      f0  Linux/PA-RISC b
12  Compaq diagnost 5c  Priam Edisk     a9  NetBSD          f1  SpeedStor      
14  Hidden FAT16 <3 61  SpeedStor       ab  Darwin boot     f4  SpeedStor      
16  Hidden FAT16    63  GNU HURD or Sys af  HFS / HFS+      f2  DOS secondary  
17  Hidden HPFS/NTF 64  Novell Netware  b7  BSDI fs         fb  VMware VMFS    
18  AST SmartSleep  65  Novell Netware  b8  BSDI swap       fc  VMware VMKCORE 
1b  Hidden W95 FAT3 70  DiskSecure Mult bb  Boot Wizard hid fd  Linux raid auto
1c  Hidden W95 FAT3 75  PC/IX           bc  Acronis FAT32 L fe  LANstep        
1e  Hidden W95 FAT1 80  Old Minix       be  Solaris boot    ff  BBT            

Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'.

Command (m for help): p
Disk /dev/nvme0n2: 20 GiB, 21474836480 bytes, 41943040 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x31fc34c5

Device         Boot Start      End  Sectors Size Id Type
/dev/nvme0n2p1       2048 20973567 20971520  10G 8e Linux LVM

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

[root@SAN-server ~]# pvcreate /dev/nvme0n2p1
  Physical volume "/dev/nvme0n2p1" successfully created.
[root@SAN-server ~]# vgcreate iscsi_vg /dev/nvme0n2p1 
  Volume group "iscsi_vg" successfully created
[root@SAN-server ~]# lvcreate -n iscsi_store -l 100%VG iscsi_vg
  Logical volume "iscsi_store" created.
  
#接下来通过targetcli 工具来做SAN网络共享
[root@SAN-server ~]# targetcli
Warning: Could not load preferences file /root/.targetcli/prefs.bin.
targetcli shell version 2.1.53
Copyright 2011-2013 by Datera, Inc and others.
For help on commands, type 'help'.

/> backstores/block create name=iscsi_store dev=/dev/iscsi_vg/iscsi_store 
Created block storage object iscsi_store using /dev/iscsi_vg/iscsi_store.

/> iscsi/ create iqn.2022-01.com.example:iscsi.server
Created target iqn.2022-01.com.example:iscsi.server.
Created TPG 1.
Global pref auto_add_default_portal=true
Created default portal listening on all IPs (0.0.0.0), port 3260.

/> cd iscsi/iqn.2022-01.com.example:iscsi.server/
/iscsi/iqn.20...:iscsi.server> cd tpg1/
/iscsi/iqn.20...i.server/tpg1> luns/ create /backstores/block/iscsi_store 
Created LUN 0.

/iscsi/iqn.20...i.server/tpg1> acls/ create iqn.2022-01.com.example:iscsi.client
Created Node ACL for iqn.2022-01.com.example:iscsi.client
Created mapped LUN 0.

/iscsi/iqn.20...i.server/tpg1> portals/ create 192.168.253.128 3260
Using default IP port 3260
Could not create NetworkPortal in configFS

/iscsi/iqn.20...i.server/tpg1> set attribute authentication=0
Parameter authentication is now '0'.
/iscsi/iqn.20...i.server/tpg1> set attribute generate_node_acls=0
Parameter generate_node_acls is now '0'.

/iscsi/iqn.20...i.server/tpg1> cd ..
/iscsi/iqn.20...:iscsi.server> cd ..
/iscsi> cd ..
/> saveconfig 
Configuration saved to /etc/target/saveconfig.json
/> exit
Global pref auto_save_on_exit=true
Last 10 configs saved in /etc/target/backup/.
Configuration saved to /etc/target/saveconfig.json

[root@SAN-server ~]# targetcli
targetcli shell version 2.1.53
Copyright 2011-2013 by Datera, Inc and others.
For help on commands, type 'help'.

/> ls
o- / ........................................................................ [...]
  o- backstores ............................................................. [...]
  | o- block ................................................. [Storage Objects: 1]
  | | o- iscsi_store ... [/dev/iscsi_vg/iscsi_store (10.0GiB) write-thru activated]
  | |   o- alua .................................................. [ALUA Groups: 1]
  | |     o- default_tg_pt_gp ...................... [ALUA state: Active/optimized]
  | o- fileio ................................................ [Storage Objects: 0]
  | o- pscsi ................................................. [Storage Objects: 0]
  | o- ramdisk ............................................... [Storage Objects: 0]
  o- iscsi ........................................................... [Targets: 1]
  | o- iqn.2022-01.com.example:iscsi.server ............................. [TPGs: 1]
  |   o- tpg1 .............................................. [no-gen-acls, no-auth]
  |     o- acls ......................................................... [ACLs: 1]
  |     | o- iqn.2022-01.com.example:iscsi.client ................ [Mapped LUNs: 1]
  |     |   o- mapped_lun0 .......................... [lun0 block/iscsi_store (rw)]
  |     o- luns ......................................................... [LUNs: 1]
  |     | o- lun0  [block/iscsi_store (/dev/iscsi_vg/iscsi_store) (default_tg_pt_gp)]
  |     o- portals ................................................... [Portals: 1]
  |       o- 0.0.0.0:3260 .................................................... [OK]
  o- loopback ........................................................ [Targets: 0]
/> exit

3.2 客户端配置

#客户端
[root@wentan ~]# hostnamectl set-hostname SAN-client
[root@wentan ~]# bash
#安装iscsi看客户端初始化工具
[root@SAN-client ~]# yum install -y iscsi-initiator-utils

[root@SAN-client ~]# vim /etc/iscsi/initiatorname.iscsi 
InitiatorName=iqn.2022-01.com.example:iscsi.client

#接下来允许iscsi服务,开启iscsi服务
[root@SAN-client ~]# systemctl enable iscsi iscsid.service 
Created symlink /etc/systemd/system/remote-fs.target.wants/iscsi.service → /usr/lib/systemd/system/iscsi.service.
Created symlink /etc/systemd/system/multi-user.target.wants/iscsid.service → /usr/lib/systemd/system/iscsid.service.
[root@SAN-client ~]# systemctl start iscsi iscsid.service 

#接下来通过iscsi的发现机制  来发现对方ip地址是否有共享给我的存储
[root@SAN-client ~]# iscsiadm -m discovery -t st -p 192.168.253.128
192.168.253.128:3260,1 iqn.2022-01.com.example:iscsi.server

#选择自动的挂上SAN
[root@SAN-client ~]# iscsiadm -m node -l
Logging in to [iface: default, target: iqn.2022-01.com.example:iscsi.server, portal: 192.168.253.128,3260]
Login to [iface: default, target: iqn.2022-01.com.example:iscsi.server, portal: 192.168.253.128,3260] successful.

#接下来发现这块设备,发现名字为sda  大小为10G
[root@SAN-client ~]# lsblk 
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda             8:0    0   10G  0 disk 
sr0            11:0    1 1024M  0 rom  
nvme0n1       259:0    0   25G  0 disk 
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0   24G  0 part 
  ├─rhel-root 253:0    0   22G  0 lvm  /
  └─rhel-swap 253:1    0    2G  0 lvm  [SWAP]

#我们需要对这块硬盘做分区
[root@SAN-client ~]# fdisk /dev/sda 

Welcome to fdisk (util-linux 2.32.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0x80e3c182.

Command (m for help): n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-20963327, default 2048): 
Last sector, +sectors or +size{K,M,G,T,P} (2048-20963327, default 20963327): +5G

Created a new partition 1 of type 'Linux' and of size 5 GiB.

Command (m for help): p
Disk /dev/sda: 10 GiB, 10733223936 bytes, 20963328 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 1048576 bytes
Disklabel type: dos
Disk identifier: 0x80e3c182

Device     Boot Start      End  Sectors Size Id Type
/dev/sda1        2048 10487807 10485760   5G 83 Linux

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

#把分区做成文件系统 ext4格式
[root@SAN-client ~]# mkfs.ext4 /dev/sda1 
mke2fs 1.44.3 (10-July-2018)
Creating filesystem with 1310720 4k blocks and 327680 inodes
Filesystem UUID: ac62797b-da6c-4bf3-a09b-7808b6081ebf
Superblock backups stored on blocks: 
	32768, 98304, 163840, 229376, 294912, 819200, 884736

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done

#编辑自动挂载列表
[root@SAN-client ~]# vim /etc/fstab
/dev/sda1       /SAN    ext4    defaults        0 0
[root@SAN-client ~]# mkdir /SAN
[root@SAN-client ~]# mount -a
[root@SAN-client ~]# df -hT
Filesystem            Type      Size  Used Avail Use% Mounted on
devtmpfs              devtmpfs  1.9G     0  1.9G   0% /dev
tmpfs                 tmpfs     1.9G     0  1.9G   0% /dev/shm
tmpfs                 tmpfs     1.9G   10M  1.9G   1% /run
tmpfs                 tmpfs     1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/rhel-root xfs        22G  4.2G   18G  19% /
/dev/nvme0n1p1        xfs      1014M  169M  846M  17% /boot
tmpfs                 tmpfs     376M   16K  376M   1% /run/user/42
tmpfs                 tmpfs     376M  4.6M  372M   2% /run/user/1000
tmpfs                 tmpfs     376M  4.0K  376M   1% /run/user/0
/dev/sda1             ext4      4.9G   20M  4.6G   1% /SAN

#到这里就全都成功了

四、归档和（解）压缩

归档和压缩的区别

归档就是把多个文件归到一起，他不是压缩，并不能压缩大小

4.1 归档

tar -cvf  归档文件夹名   归档文件1   归档文件2
tar -cvf txt  123.txt 12.txt 
解档：tar -xvf  文档名

4.2 压缩

gzip bzip两种压缩方法

Gzip：压缩速度快 压缩效率高 tar -zvcf

Bzip：压缩速率慢 压缩比例高 节省空间 tar -jvcf

[root@SAN-server dwt]# tar -zvcf gd.tar.gz test.pdf 222.txt 321.txt 
test.pdf
222.txt
321.txt
[root@SAN-server dwt]# tar -jvcf gd.tar.bz test.pdf 222.txt 321.txt 
test.pdf
222.txt
321.txt
[root@SAN-server dwt]# ll
total 7796
-rw-r--r--. 1 root root        13 Jan 15 11:23 222.txt
-rwxrw-r-x+ 1 root wentan     240 Jan 11 11:43 321.txt
drwxr-xr-x. 2 root root         6 Jan 11 11:04 back
drwxr-xr-x. 2 root root        22 Jan  8 15:21 etc
-rw-r--r--. 1 root root   2642757 Jan 19 16:00 gd.tar.bz
-rw-r--r--. 1 root root   2631479 Jan 19 15:59 gd.tar.gz
drwxr-xr-x. 2 root root         6 Jan 19 15:54 test
-rw-r--r--. 1 root root   2692317 Jan 19 15:51 test.pdf

4.3 解压缩

Gzip： tar -zvxf 压缩包名

Bzip： tar -jvxf 压缩包名

[root@SAN-server dwt]# ll
total 5156
drwxr-xr-x. 2 root root       6 Jan 11 11:04 back
drwxr-xr-x. 2 root root      22 Jan  8 15:21 etc
-rw-r--r--. 1 root root 2642757 Jan 19 16:00 gd.tar.bz
-rw-r--r--. 1 root root 2631479 Jan 19 15:59 gd.tar.gz
drwxr-xr-x. 2 root root       6 Jan 19 15:54 test
[root@SAN-server dwt]# tar -zvxf gd.tar.gz
test.pdf
222.txt
321.txt
[root@SAN-server dwt]# ll
total 7796
-rw-r--r--. 1 root root        13 Jan 15 11:23 222.txt
-rwxrw-r-x. 1 root wentan     240 Jan 11 11:43 321.txt
drwxr-xr-x. 2 root root         6 Jan 11 11:04 back
drwxr-xr-x. 2 root root        22 Jan  8 15:21 etc
-rw-r--r--. 1 root root   2642757 Jan 19 16:00 gd.tar.bz
-rw-r--r--. 1 root root   2631479 Jan 19 15:59 gd.tar.gz
drwxr-xr-x. 2 root root         6 Jan 19 15:54 test
-rw-r--r--. 1 root root   2692317 Jan 19 15:51 test.pdf

不管是压缩还是归档都是：

压缩命令+ 压缩后文件包的名+ 需要压缩的文件（可以好多个）

建议GZIP文件是以tar.gz结尾

BZIP文件是以tar.bz结尾

五、Linux内核

内核就是操作系统的核心部分

5.1 redhat内核的功能：

1.系统初始化：检测硬件资源并启动系统

2.进程调度 ： 决定进程什么时候运行，以及运行多久

3.内存管理： 给运行的进程分配内存

4.安全：支持权限，支持selinux ，支持防火墙 支持iptables

5.支持标准网络，文件系统

具体可以参考kernel-doc

5.2 内核的组成

多个内核版本可以共存的

内核的组成如下

/boot/vmlinuz-4.18.0-80.el8.x86_64 启动时用到的内核

/boot/initramfs-4.18.0-80.el8.x86_64.img 启动时提供必要模块的内核

/lib/modules/版本/内核模块

5.3 虚拟的文件系统/proc

进程信息 /proc/PID(数字)

cpu信息 /proc/cpuinfo

内存资料 /proc/meminfo

磁盘信息 /proc/partition

5.4 sysctl 配置内核参数

当前生效的内核配置参数都在 /pro/sys/

内核参数配置文件 /etc/sysctl.conf 系统启动时读取的参数

sysctl -a 显示所有的内核模块

一定要结合grep来使用

5.5 内核模块

内核模块： /lib/modules/内核版本

内核模块的相关命令：

lsmod 查看内核已经加载的模块

modinfo 模块名 查看这个模块的详细信息

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