Virtual Machine Windows Disk Zeroing Tool - sdelete
To reduce disk, sdelete
can be used to write zero in unused space. It can be downloaded from following website
https://docs.microsoft.com/en-us/sysinternals/downloads/sdelete
To reduce disk, sdelete
can be used to write zero in unused space. It can be downloaded from following website
https://docs.microsoft.com/en-us/sysinternals/downloads/sdelete
The software can be downloaded from following website
The software can be downloaded from following website.
https://www.softpedia.com/get/Network-Tools/Misc-Networking-Tools/SnmpWalk.shtml
https://download.cnet.com/SnmpWalk/3000-2085_4-75795880.html
When using ubuntu GUI VPN connection, the DNS might not be updated correctly. Following command can be used to update search domain and DNS server.
sudo systemd-resolve --interface tun0 --set-dns <dns_server> --set-domain <domain>
Note: The latest test in VPN GUI, the DNS setting is working as expected.
For openvpn command line,
openvpn --config client.ovpn --script-security 2 --up ./manual-config
The manual-config
script can be as follow
#!/bin/sh
set -e
resolvectl dns $dev 192.0.2.53 192.0.2.54
resolvectl domain $dev "~foo.example.com" "~bar.example.com"
resolvectl dnssec $dev off
or
#!/bin/sh
systemd-resolve -i $dev \
--set-dns=192.0.2.53 --set-dns=192.0.2.54 \
--set-domain=foo.example.com --set-domain=bar.example.com \
--set-dnssec=off # <- Not super nice, but might be needed.
Another method is to use /etc/openvpn/update-systemd-resolved
script, which is in openvpn-systemd-resolved
package,
openvpn \
--config client.ovpn \
--up /etc/openvpn/update-systemd-resolved \
--down /etc/openvpn/update-systemd-resolved \
--down-pre \
To allow DNS and other options applied to new interface, a dispatcher file can be created, for example, /etc/NetworkManager/dispatcher.d/10-openvpn-tun0-up
. The content can be as follows
#!/usr/bin/env bash
interface=$1
event=$2
if [[ $interface != "tun0" ]] || [[ $event != "up" ]]
then
return 0
fi
# place your commands bellow this line
resolvectl dns tun0 192.168.1.1 192.168.1.2
resolvectl domain tun0 "~new.com"
Systemd-resolved DNS configuration for VPN
Network Manager script when interface up?
.ssh/config
Host <host>
port <new_port>
user <new_user>
IdentityFile <new_file>
Introduction to AWS Networking
AWS VPC Basics - Understanding what is VPC and Calculating CIDR for VPC and Subnets
The ansible command default module is command
. So following commands are the same
ansible -i inventory multi -m command -a "date"
ansible -i inventory multi -a "date"
For idempotence, can update_cache task
Testing Ansible roles using Molecule.
Timeout in 3600 seconds.
ansible -i inventory multi -b -B 3600 -P 0 -a "yum -y update"
Using -P
for seconds
ansible -i inventory multi -b -B 3600 -P 0 -a "yum -y update"
The result shows ansible job ID, which can be used to query in the server.
192.168.60.6 | CHANGED => {
...
"ansible_job_id": "991487770448.3711",
...
"results_file": "/root/.ansible_async/991487770448.3711",
...
}
Query by job id
ansible -i inventory db -b -m async_status -a "jid=991487770448.3711"
*Note: This will not show log or error of job"
ansible -i inventory multi -b -a "tail /var/log/messages"
ansible -i inventory multi -b -m shell -a "tail /var/log/messages | grep ansible-command | wc -l"
ansible -i inventory multi -b -m cron -a "name=something hour=4 job=/path/to/script.sh"
ansible -i inventory multi -b -m cron -a "name=something hour=4 job=/path/to/script.sh state=absent"
ansible -i inventory multi -b -m git -a "repo=github_url_goes_here dest=/opt/app update=yes version=1.2.4"
Ansible configuration file ansible.cfg
[ssh_connection]
pipelining = True
Destroy VMs
vagrant destroy -f
mkdir playbooks
cd playbooks
[ec2]
35.175.148.144
[ec2:vars]
ansible_user=centos
ansible_ssh_private_key_file=~/.ssh/jeffgeerling_aws.pem
shell-script.sh
# Install Apache.
yum install --quiet -y httpd httpd-devel
# Copy configuration files.
cp httpd.conf /etc/httpd/conf/httpd.conf
cp httpd-vhosts /etc/httpd/conf/httpd-vhosts.conf
# Start Apache and configure it to run at boot.
service httpd start
chconfig httpd on
playbook.yml
---
- name: Install Apache.
hosts: all
tasks:
- name: Install Apache
command: yum install --quiet -y httpd httpd-devel
- name: Copy configuration files.
command: >
cp httpd.conf /etc/httpd/conf/httpd.conf
- command: >
cp httpd-vhosts /etc/httpd/conf/httpd-vhosts.conf
- name: Start Apache and configure it to run at boot.
command: service httpd start
- command: chkconfig httpd on
or
---
- name: Install Apache.
hosts: all
tasks:
- name: Install Apache
shell: |
yum install --quiet -y httpd httpd-devel
cp httpd.conf /etc/httpd/conf/httpd.conf
cp httpd-vhosts /etc/httpd/conf/httpd-vhosts.conf
- name: Start Apache and configure it to run at boot.
command: service httpd start
- command: chkconfig httpd on
or
---
- name: Install Apache.
hosts: all
become: true
tasks:
- name: Install Apache
yum:
name:
- httpd
- httpd-devel
state: present
become: true
- name: Copy configuration files.
copy:
src: "{{ item.src }}"
dest: "{{ item.dest }}"
owner: root
group: root
mode: 0644
with_items:
- src: httpd.conf
dest: /etc/httpd/config/httpd.conf
- src: httpd-vhosts.conf
dest: /etc/httpd/conf/httpd-vhosts.conf
- name: Make sure Apache is started now and at boot.
service:
name: httpd
state: started
enabled: true
- command: >
cp httpd-vhosts /etc/httpd/conf/httpd-vhosts.conf
- name: Start Apache and configure it to run at boot.
command: service httpd start
- command: chkconfig httpd on
run on all nodes except one
ansible-playbook -i inventory multi --limit db
ansible-playbook -i inventory multi --limit=192.168.60.6
ansible-playbook -i inventory multi --limit="!:db"
ansible-inventory --list i inventory