Linux system upgrade configurations

Linux system upgrade configurations

1. Disable IPV6

Vi/etc/sysconfig/network

NETWORKING_IPV6 = no # Drop

Source/etc/sysconfig/network

Vi/etc/modprobe. conf

Add alias net-pf-10 off
Alias ipv6 off

2. Disable shutdown and restart permissions for normal users (control permissions)

Vi/etc/inittab

Comment out ca: ctrlaltdel;/sbin/shutdown-t3-rnow (disable hot start)

3. User Access Control (I did not use this operation for company reasons)

Vi/etc/hosts. deny

Add; ALL: ALL access from any IP address is not allowed

Vi/etc/hosts. allow

Sshd: 192.168.2.10 allows ssh logon with an IP address of 10

4. Modify the alias file

Vi/etc/aliases

Comment out the following content: games ingres system toor manager dumper decode root may contain operator

5. Disable PIN access and enter

Echo 1>/proc/sys/net/ipv4/icmp_echo_ignore_all

Change echo 1 to echo 0 for recovery.

6. Prohibit source routing (generally prohibited)

Echo 0>/proc/sys/net/ipv4/conf/all/accept_source_route
Echo 0>/proc/sys/net/ipv4/conf/default/accept_source_route
Echo 0>/proc/sys/net/ipv4/conf/eth0/accept_source_route
Echo 0>/proc/sys/net/ipv4/conf/eth1/accept_source_route
Echo 0>/proc/sys/net/ipv4/conf/lo/accept_source_route

7. Prevent SYN Attacks

Echo 1>/proc/sys/net/ipv4/tcp_syncookies