A network configuration
Network card type
IP address acquisition method dhcp or none=static default none
NAME
DEVICE
(HWADDR=) mac address
boot
ip address
Subnet mask NETMASK
Gateway
DNS1
DNS2
systemctl restart network restart network
services network restart (command before 7)
route -n routing table to see if the gateway takes effect
cat /etc/resolv.conf DNS automatically generated
ifconfig
ip a =ip appr list view all network cards
Two modify the host name
hostnamectl set-hostname it101 takes effect immediately
vim /etc/hostname can also modify the file
Configure the hosts file to access the corresponding computer without DNS
vim /etc/hosts ip address corresponds to the name of the computer
192.168.1.1 zl
Three planning tasks
crontab periodic scheduled task blank space
Minute time day month week (0 and 7 are Sundays / every-to, and)
*/5 10-18 1-5,8 * * /data/backup.sh command The day and the week conflict, do not write at the same time
crontab -e edit scheduled task
crontab -l view scheduled tasks
crontab -r delete scheduled task
Absolute path is required for commands or files
/etc/cron/deny plan permission denied
Four SSH management
The openssh-server openssh-clients package is installed by default to release the ssh protocol
systemctl status sshd View service status enabled boot operation
systemctl stop sshd
systemctl restart sshd
systemctl enable sshd starts automatically at boot
systemctl disable sshd does not start at boot
netstat -tulnp |grep :22/sshd
View listening port
/etc/services View the relationship between services and ports
ssh [email protected] remote connection
scp test.txt [email protected]:/root remote copy -r copy folder
Password-free login, key login ssh mutual trust
ssh-keygen generates public and private keys is_rsa id_rsa.pub
ssh-copy-id -i /root/.ssh/id_rsa.pub 192.168.6.31 target ip
The target end /etc/ssh/sshd_config can be changed ssh port port changed to -p
Line 49 can ssh root be allowed to log in
79-line password login permission
129 Check DNS default xshell connection slow changed to no
Five process management PID is not fixed
ps aux |more Process management? The process that runs before the system boots and logs in to the interface
ps -ef
End of process
kill -15 pid -15 can be omitted by default
kill -9
15 Normal end 9 Forced end