Tuesday, May 16, 2017

Proxy PAC Tester

I wrote this .NET program to parse the PAC file and test its exception. This provides the GUI, rather than using google unsupported CLI code.


It supports direct fetch from the URL or static PAC file.

Sunday, April 30, 2017

Ubuntu CIFS Mount to Windows

To support SMB2 mount from Ubuntu to Windows, edit the fstab file and include this:

//windows.domain.local/share/folder /mount/point cifs credentials=/root/.credentials,vers=2.0,iocharset=utf8,sec=ntlm,dir_mode=0770,uid=33,gid=33 0 0

Monday, March 06, 2017

VCP6-NV Today

Yay!! Passed 2V0-641 exam day. Officially VCP6-NV Today. NSX NSX NSX :)


Thursday, February 02, 2017

Bitbucket Installation

I have a need to create code repository locally. I don't want to use code repo in the cloud. Bitbucket is the winner!

#1 - Install Ubuntu 16.10
Download from ubuntu.com, get the latest ISO file, boot and install.
During the installation wizard, make sure PostgreSQL is selected and installed.

#2 - Configure PostgreSQL
Login to ubuntu as the standard user

> sudo -u postgres psql postgres

\password mynewpassword
\q

>

#3 - Create PostgreSQL Database and Role

> sudo -u postgres
CREATE ROLE bitbucketuser WITH LOGIN PASSWORD 'mypassword' VALID UNTIL 'infinity';

CREATE DATABASE bitbucket WITH ENCODING='UTF8' OWNER=bitbucketuser CONNECTION LIMIT=-1;

\q

>

#4 - Install Bitbucket
Download the bitbucket installer from atlassian.com
Change the file permission to execute +x
Run it

#5 - Configure Bitbucket
During the configuration wizard, when asked for database, specify localhost, bitbucket as the database, bitbuckeruser and the user and 'mypassword' as the password


Sunday, January 01, 2017

Office 365 & Squid

I had an issue today. My Outlook does not want to connect to office 365 when I setup IE to use SQUID for the proxy. Apparently some of the O365 URLs are resolving up to 25 IP Addresses and depending on the location, some of the connection might get rejected.

By default SQUID only tries the first 10 connections. To change this, edit the squid.conf and add:

forward_max_tries 25

save, restart SQUID instance. Enjoy

Thursday, December 01, 2016

Proxy Enforcer

I developed this little utility while doing proxy migration project. This utility helps me to enforce the Windows proxy settings to IE.


You can add Proxy by clicking the "Add Proxy" button, which gives you the same configuration like Windows


Once your proxy setting is added to the list, highlight the proxy and click "Select Proxy" to enforce the selected proxy to your IE. The program will run on the TaskBar. 



Wednesday, November 16, 2016

Ubuntu File Finders

To find the Disk Usage:

#> sudo du -sx /* 2> /dev/null | sort -n

To deep dive

#> sudo du -sx /var/* 2> /dev/null | sort -n

To find files bigger than something

#> sudo find / -size +10M -ls

Wednesday, October 26, 2016

Windows 2012 R2 - File Backup

I need to backup my files running on Windows 2012 R2 to external drive. I also need this to be done in a regular basis and send me an email after the job done with the report.

First, I create a batch file, called backup.bat, with the content

@echo off
robocopy H:\Home V:\Home /MIR /R:1 /W:1 /LOG:V:\Home.txt
robocopy K:\Documents V:\Documents /MIR /R:1 /W:1 /LOG:V:\Documents.txt
copy /b V:\Documents.txt +V:\Home.txt V:\Backup.txt

The last line is joining the 2 log files into a single file, backup.txt

Schedule this daily with the Windows Scheduler, having an actions:

Start a Program: cmd.exe
Add arguments: /c D:\scripts\backup.bat

That bit is done for backup job.

Now, the email bit. I create a powershell script, called email.ps1, with the content:

 function sendMail{

     Write-Host "Sending Email"

     #SMTP server name
     $smtpServer = "smtprelay.domain.local"

     #Creating a Mail object
     $msg = new-object Net.Mail.MailMessage

     #Creating SMTP server object
     $smtp = new-object Net.Mail.SmtpClient($smtpServer)

     #Email structure 
     $msg.From = "backup@mydomain.id.au"
     $msg.ReplyTo = "backup@mydomain.id.au"
     $msg.To.Add("me@mydomain.id.au")
     $msg.subject = "Backup Email - Daily"
     $msg.body = "Backup Email - Daily"
     $attachment = New-Object System.Net.Mail.Attachment("V:\Backup.txt", 'text/plain')
     $msg.Attachments.Add($attachment)

     #Sending email 
     $smtp.Send($msg)
  
}

#Calling function

sendMail 

The email powershell script attach the backup.txt file and send it away
On the same schedule job created earlier, add a second action:

Start a Program: powershell
Add arguments: D:\scripts\email.ps1

Done. Second action will be executed after the 1st action is running and it will grab the log and attach it to the email.

Friday, September 30, 2016

Westpac CISO Award

I got the CISO Award!! It was a surprise for me who just started with Westpac Security team for 8 months.

Tuesday, September 06, 2016

Monday, August 01, 2016

OwnCloud Manual Upgrade

I adopted the below methods from upgrading Wordpress manually and tweak the process for manually upgrading OwnCloud:

Backup
Navigate to your OwnCloud location and run the following to backup your OwnCloud.

rsync -a owncloud/ owncloud.backup/

Download Latest OwnCloud 

wget https://download.owncloud.org/community/owncloud-9.1.1.tar.bz2

replace the link with the latest bz2 file.

Extract the Package

bzip2 -d owncloud-9.1.1.tar.bz2
tar xvf owncloud-9.1.1.tar

this creates "owncloud" directory

Copy the Updated Files

rsync -rtv new_path_version/owncloud/ old_path_version/owncloud/

this syncs any file that has been changed from the new location/version to the old location

Navigate to The Site

Load the site and it will ask you to upgrade the database. Don't do it over the UI, do it manually

Database Upgrade Manually

run the following command from the "owncloud" directory

To test the database upgrade:

sudo -u www-data php occ upgrade --dry-run -v

To execute the database upgrade:

sudo -u www-data php occ upgrade -v






Wednesday, July 13, 2016

Dynamic DNS for Ubuntu

I am using opendns.com to protect my network at home. My IP isn't static, so I need a way to update opendns.com with my IP if that changes.

I am running ubuntu, so let's start with installing ddclient

sudo apt-get install ddclient

and then edit ddclient.conf

sudo vi /etc/ddclient.conf

I use the following config

use=web, web=myip.dnsomatic.com
ssl=yes
server=updates.opendns.com
protocol=dyndns2
login=<open-dns-username>
password=<open-dns-password>
<open-dns-label>

Wednesday, June 22, 2016

Ubuntu Apt-Get Proxy

To have Ubuntu apt-get connection proxies via your proxy, do the following

sudo vi /etc/apt/apt.conf

Add the following line:

Acquire::http::Proxy "http://yourproxy.tld:port";

save and fire away

Monday, May 16, 2016

PowerShell - Mount BitLocker Encrypted VHD

If you have .VHD BitLocker encrypted files and would like to mount it using PowerShell:

$ss = Read-Host "Enter BitLocker Password:" -AsSecureString

Mount-VHD <path-to-VHD>\Example.VHD

#Check your disk manager which drive letter the volume is assigned to the VHD

Unlock-BitLocker -MountPoint <drive letter> -Password $ss


Monday, April 11, 2016

Windows 2012 R2 ISO to USB

Need to rebuild my drop-dead Windows 2012 R2 server.
There is no way to burn the 5.4GB ISO to my single layer 4.7GB DVD media.

So the only way is to USB boot it, here is how.

Format your USB drive - FAT32 ONLY. Make sure it is format with Master Boot Record scheme.
Plug in to your machine

Download your Windows 2012 R2 ISO file

Download Windows 7 USB/DVD Download Tool here

Install Windows 7 USB/DVD Download Tool

Run it and select your ISO and target your USB

Done

Wednesday, March 16, 2016

.NET Executing Assembly Location

During coding, if you want to reference another file, such as configuration file, text file or XML file that is located on the same location where your binary/library is you can use the following:''

string location = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);

Have fun coding :)

Sunday, February 07, 2016

UNIX Screen - Split Screen

You can do it in screen the terminal multiplexer.
  • To split vertically: ctrla then |.
  • To split horizontally: ctrla then S (uppercase one).
  • To un-split: ctrla then Q (uppercase one).
  • To switch from one to the other: ctrla then tab
Note: After splitting, you need to go into the new region and start a new session via ctrla then c before you can use that area.
EDIT, basic screen usage:
  • New terminal: ctrla then c.
  • Next terminal: ctrla then space.
  • Previous terminal: ctrla then backspace.
  • N'th terminal ctrla then [n](works for n∈{0,1…9})
  • Switch between terminals using list: ctrla then " (useful when more than 10 terminals)
  • Send ctrla to the underlying terminal ctrla then a.

Friday, January 29, 2016

Passed Cisco 300-320 Exam Today!

Had to sit on the Cisco 300-320 exam today to extend my Cisco certifications for another 3 years.
Officially still CCNP and CCDP

Friday, December 25, 2015

Fail2ban BAN-Forever!

OK, enough is enough. As per my previous blog about setting up fail2ban, there was this one persistent idiot who kept trying to break in my network. Due to fail2ban default setting, which un-bans previously banned IP, he could keep trying and trying and trying...

So, I came across this blog and set my systems as per following:

Modify fail2ban config:

vi /etc/fail2ban/fail2ban.conf
Make sure

log level = 3
logtarget = /var/log/fail2ban.log
Modify Logrotate config:

vi /etc/logrotate.d/fail2ban
Make sure

notifempty
monthly
rotate 13
missingok
postrotate
fail2ban-client set logtarget /var/log/fail2ban.log >/dev/null
endscript
# If fail2ban runs as non-root it still needs to have write access
# to logfiles.
# create 640 fail2ban adm
create 640 root adm
Add Repeat Offender rule:

vi /etc/fail2ban/jail.local
Add the following to the bottom of the line. This sets any IP that has been failing 10 times for a period of 365 days will be banned forever

#
# Repeated Offender to be banned forever
# if has been baned 10 times for 1 year
#
[repeatoffender]

enabled  = true
filter   = repeatoffender
action   = repeatoffender[name=repeatoffender]
           sendmail-whois[name=Repeat-Offender, dest=me@domain.me, sender=fail2ban@domain.me]
logpath  = /var/log/fail2ban*
maxretry = 10
findtime = 31536000
bantime  = -1
Create fail2ban Filter:

vi /etc/fail2ban/filter.d/repeatoffender.conf
Add the following to the file:

# Fail2ban configuration file
# this filter monitors the fail2ban log file and permanently bans the IP
#
# only works with iptables

[Definition]
_jailname = repeatoffender
failregex = fail2ban.actions:\s+WARNING\s+\[(?:.*)\]\s+Ban\s+
ignoreregex = fail2ban.actions:\s+WARNING\s+\[%(_jailname)s\]+Ban\s+
Create fail2ban Action:

vi /etc/fail2ban/action.d/repeatoffender.conf
Add the following to the file:

# Fail2Ban configuration File
#
#

[INCLUDES]

before = iptables-blocktype.conf

[Definition]

# Option: actionstart
# Notes.: command executed once at the start of fail2ban
# Values: CMD

actionstart = iptables -N fail2ban-
              iptables -A fail2ban- -j RETURN
              iptables -I  -p  -j fail2ban-
              # Establish chain and blocks for saved IPs
              iptables -N fail2ban-ip-blocklist
              iptables -A fail2ban-ip-blocklist -j RETURN
              iptables -I  -p  -j fail2ban-ip-blocklist 
              cat /etc/fail2ban/ip.blocklist. |grep -v ^\s*#|awk '{print $1}' | while read IP; do iptables -I fail2ban-ip-blocklist 1 -s $IP -j REJECT --reject-with icmp-port-unreachable; done

# Option:  actionstop
# Notes.:  command executed once at the end of Fail2Ban
# Values:  CMD
#
actionstop = iptables -D  -p  -j fail2ban-
             iptables -F fail2ban-
             iptables -X fail2ban-
             # Remove chain and blocks for saved IPs to prevent duplicates on service restart
             iptables -D  -p  -j fail2ban-ip-blocklist
             iptables -F fail2ban-ip-blocklist
             iptables -X fail2ban-ip-blocklist

# Option:  actioncheck
# Notes.:  command executed once before each actionban command
# Values:  CMD
#
actioncheck = iptables -n -L  | grep -q 'fail2ban-[ \t]'

# Option:  actionban
# Notes.:  command executed when banning an IP. Take care that the
#          command is executed with Fail2Ban user rights.
# Tags:    See jail.conf(5) man page
# Values:  CMD
#
actionban = VERIFY="*"
            ADD="        # fail2ban/$( date '+%%Y-%%m-%%d %%T' ): Perma-Banned"
            FILE=/etc/fail2ban/ip.blocklist.
            grep -q "$VERIFY" "$FILE" || iptables -I fail2ban-  1 -s  -j DROP
            grep -q "$VERIFY" "$FILE" || echo "$ADD" >> "$FILE"

# Option:  actionunban
# Notes.:  command executed when unbanning an IP. Take care that the
#          command is executed with Fail2Ban user rights.
# Tags:    See jail.conf(5) man page
# Values:  CMD
#
actionunban = # Do nothing becasuse their IP is in the blocklist file

# To manually unban from the ip blocklist file run this command:
# Be warned that if the ip is in log rotated files it must be whitelisted
#
# sed -i '/^/d' /etc/fail2ban/ip.blocklist.repeatoffender
#

[Init]

# Default name of the chain
#
name = default

# Option:  protocol
# Notes.:  internally used by config reader for interpolations.
# Values:  [ tcp | udp | icmp | all ] Default: tcp
#
protocol = tcp

# Option:  chain
# Notes    specifies the iptables chain to which the fail2ban rules should be
#          added
# Values:  STRING  Default: INPUT
chain = INPUT
that's it. to check the iptables, to show which IP is blocked there, just run:

iptables -L -n



Sunday, November 22, 2015

Bigpond SMTP Fails

That's right! my Bigpond Internet service fails to deliver!

Fail 1
It does not allow outbound SMTP from my network to anywhere else except their own SMTP server

Fail 2
It has got limited number email relay allowed per day or month

I understand this to block their customers become spammer. However, their solution is stereotyping every single one of their customers as spammers.

To avoid this I use gmail to relay my email, bypassing bigpond all together.
So what I did:

Create a new gmail account - specifically used for relaying only, which a very strong password

then

Install required software

sudo apt-get install mailutils libsasl2-2 ca-certificates libsasl2-modules
Create Gmail credential file

vi /etc/postfix/sasl_passwd
add the following content

[smtp.gmail.com]:587    USERNAME@gmail.com:PASSWORD
Modify the credential file permissions

sudo chmod 400 /etc/postfix/sasl_passwd
sudo postmap /etc/postfix/sasl_passwd
Copy the CA certificate

cat /etc/ssl/certs/Thawte_Premium_Server_CA.pem | sudo tee -a /etc/postfix/cacert.pem
Modify main.conf and add the following line

relayhost = [smtp.gmail.com]:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_tls_CAfile = /etc/postfix/cacert.pem
smtp_use_tls = yes
Reload

sudo /etc/init.d/postfix reload
Now my outbound SMTP relay is going through Gmail SMTP server authenticated.