April 2025
M T W T F S S
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Categories

April 2025
M T W T F S S
 123456
78910111213
14151617181920
21222324252627
282930  

Remove APF Firewall

How to Remove APF Firewall

# ser­vice ipt­a­bles stop

# chk­con­fig apf off

# /bin/rm –rfv /etc/apf

# /bin/rm –fv /etc/cron.daily/fw

# /bin/rm –fv /etc/init.d/apf

# ipt­a­bles –L –n

IPTABLES Rules

Limiting Spam and Attacks Security – Training You can use a bridge to effectively limit spam and attacks by managing the IP Ranges per Country.The basis behind the thought here is that these IP Address Ranges probably do not need access to your network in any way, unless you are an International business. By blocking […]

VSFTP

CentOS 6

vsftpd 2.2.2

su – root

yum install vsftpd

cd /etc/vsftpd/

vi config

anonymous_enable=NO This is set to YES by default.

local_enable=YES This is set to NO by default and change when you want the local users to have ftp access.

xferlog_enable=Yes This is set to NO by default. Your logs will be written […]

swap issues on Linux and clear the swap usage

swap issues on Linux

clear the swap usage

free -to (Total memory usage)

free -m (Memory usage of swap)

swapoff -a && swapon -a ( swap off and on)

free

cat /proc/swaps sync; echo 3 > /proc/sys/vm/drop_caches

To free pagecache: # echo 1 > /proc/sys/vm/drop_caches

To free dentries and inodes: […]

Extending Swap on an LVM2 Logical Volume

Extending Swap on an LVM2 Logical Volume

1)Check swap space and its utilization cat /proc/swaps # free

2) Scan (all disks) for Logical Volumes lvscan [root@localhost ~]# lvscan ACTIVE ‘/dev/VolGroup/lv_root’ [47.44 GiB] inherit ACTIVE ‘/dev/VolGroup/lv_home’ [46.19 GiB] inherit ACTIVE ‘/dev/VolGroup/lv_swap’ [5.88 GiB] inherit

3) Disable devices and files for paging and swapping swapoff -v […]

Reducing Swap on an LVM2 Logical Volume

Reducing Swap on an LVM2 Logical Volume 1) Check swap space and its utilization cat /proc/swaps # free

2) Scan (all disks) for Logical Volumes lvscan

[root@localhost ~]# lvscan ACTIVE ‘/dev/VolGroup/lv_root’ [47.44 GiB] inherit ACTIVE ‘/dev/VolGroup/lv_home’ [46.19 GiB] inherit ACTIVE ‘/dev/VolGroup/lv_swap’ [5.88 GiB] inherit

3) Disable devices and files for paging and swapping swapoff […]

Centos 6 SFTP chroot Jail

Centos 6 SFTP chroot Jail

User and Group setup

First you will want to establish the sftponly group

groupadd sftponly

Then create the user with the correct home directories and group

useradd -d /var/www/vhosts/bob -s /bin/false -G sftponly bob

Don’t forget at this point to also add password to these new accounts.

SSHd configuration […]

Shorewall – Firewall

CentOS – Install and Configure Shorewall

Add repository EPEL that is provided from Fedora project. wget http://ftp.riken.jp/Linux/fedora/epel/RPM-GPG-KEY-EPEL-6 rpm –import RPM-GPG-KEY-EPEL-6 rm -f RPM-GPG-KEY-EPEL-6 vi /etc/yum.repos.d/epel.repo # create new [epel] name=EPEL RPM Repository for Red Hat Enterprise Linux baseurl=http://ftp.riken.jp/Linux/fedora/epel/6/$basearch/ gpgcheck=1 enabled=0 # when you use the repository, input yum command like follows

yum –enablerepo=epel install […]

Configure Advanced Policy-based Firewall (APF), Brute Force Detection (BFD), DDoS Deflate

Configure Advanced Policy-based Firewall (APF), Brute Force Detection (BFD), DDoS Deflate

Advanced Policy Firewall

Description: Advanced Policy Firewall (APF) is an iptables(netfilter) based firewall system designed around the essential needs of today’s Linux servers. The configuration is designed to be very informative and easy to follow. The management on a day-to-day basis is […]

IPTABLES Firewall on Centos

Firewall on Centos OS

#!/bin/sh # #

## Set your IP address MYIP=”192.168.1.108″ # ## Flush rules & reset counters /sbin/iptables -F /sbin/iptables -Z # ## Set policies /sbin/iptables -P INPUT DROP /sbin/iptables -P FORWARD DROP /sbin/iptables -P OUTPUT DROP # ## Drop all incoming fragments /sbin/iptables -A INPUT -i eth0 -f -j DROP […]