Cannot Display | Windows Tips, SysAdmin Scripts and a whole lot of tech

January 10, 2019 No Comments

WordPress redirect loop when using CloudFlare – err_too_many_redirects [Solved]

As a wordpress user, or hosting admin i’m sure you have seen it before – the dreaded err_too_many_redirects page.

This is caused by a number of issues, including:

Domain name change
Changing SSL certificate
Incorrect URL configuration
Server misconfiguration
.htaccess errors
Cookie issues
Reverse proxy issues
HTTPS issues
Plugin malfunctions
Bad WordPress upgrades
Server file permission issues
The list goes on, but you get the message…

There are countless reasons that could cause this error, and most of them are easily fixable with a quick google. However Yesterday i came across a new one.

WordPress, Cloudflare & Shared Hosting

If you came here for the Solution here it is:

Edit your wp-config.php file and at the bottom add:

if (strpos($_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false) $_SERVER['HTTPS']='on';

So what causes this?

Well, in this case it was a combination of things, this is very specific to three things in this environment. 1) Shared Hosting. 2)No root SSL Certificate. 3)CloudFlare ‘Always use HTTPS’ settings.

After taking a step back and working out the basics of what i had, and why other ‘fixes’ that usually work, weren’t- i realised what i had here, was a simply reverse proxy. That is, that where the files are hosted without SSL, but the reverse proxy (in this case CloudFlare) was using SSL.

Finally, i found this nugget in the WordPress Codex:
https://codex.wordpress.org/Administration_Over_SSL#Using_a_Reverse_Proxy

And it all clicked.

“If WordPress is hosted behind a reverse proxy that provides SSL, but is hosted itself without SSL, these options will initially send any requests into an infinite redirect loop.

And that is why we need to tell wordpress to force SSL to prevent this WordPress redirect loop when using CloudFlare.

Hope that someone finds this helpful!

January 9, 2019 No Comments

DMARC with quotes or without? [SOLVED]

Does my DMARC record need to include quotation marks or not?

9/10 times, no quotes are needed.

However, this all depends on where you edit your DNS.

In the raw DNS zone file, which is what is passed from machine to machine, the .txt record DOES need to be enclosed in quotation marks if it contains spaces. It is unlikely that your domain/DNS provider however will give you direct edit access to this, and instead will be providing their own interface to edit entries with pre-built in quotation marks. Exceptions to this can be found when directly editing via CLI at the root of a server, or when using the raw edit mode on WHM.

For example, Cloudflare will automatically wrap any string of text in a .TXT record in quotes for you, and remove extra quotes you may add,

namesco however will not automatically remove extra quotations to their already provided ones – which could lead to double quotations, and issues further down the line.

It pretty much boils down to your provider, it is best to have a quick skim of their DNS Q&A section – or to test by trial and error!

My favorite testing site is currently https://mxtoolbox.com/DMARC.aspx

July 31, 2018 No Comments

Enable disk performance in task manager, Windows Server

Can’t see the disk performance in task manager on a Windows Server?

There is multiple factors for disk performance not showing up, including raid cards, the server being nested on a HV or running as a VM, there is a simple quick fix though;

Step 1)
Open Elevated Command Prompt

Step 2)
Start disk performance counters:
diskperf –y

With any luck, that should be it now showing in Task manager, if it does not, close and re-open it for the disk performance indicators to appear.
On occasion, you may need to re-install/install the latest raid card drivers if they are missing in order for the disk performance indicators to read and run correctly.

February 21, 2018 No Comments

[SOLVED] Manually Register Acronis Backup Client for Backup Cloud

Manually Register Acronis Backup

Occasionally a backup client will disconnect, or cannot connect in the first place to obtain its backup set and process its jobs.
With pre-provisioning systems, this is often the case for certainly Mac and Linux machines.

Solution

(!) IMPORTANT: This method is NOT supported for registration of Agent for VMware (Windows)

Manually Register Acronis Backup client.
Use quotation marks, if your password contains special characters or spaces.

Windows OS
1. Open Command prompt and navigate to C:\Program Files\BackupClient\BackupAndRecovery:
cd “C:\Program Files\BackupClient\BackupAndRecovery”
2. Issue this command to register the client machine:
register_msp_mms.exe register https://cloud.acronis.com

Linux OS
1. Open terminal as root user
2. Type in the following command to register the agent:
/usr/lib/Acronis/BackupAndRecovery/AmsRegisterHelper register https://cloud.acronis.com

OS X
1. Open terminal.
2. Execute:
sudo -u root “/Library/Application Support/BackupClient/Acronis/BackupAndRecovery/AmsRegisterHelper” register https://cloud.acronis.com

From

NB: if you are outwith the normal Acronis Data Centres, as i was, then replace the cloud.acronis.com URL with the URL you use to log into your dashboard. i.e. https://eu-cloud.acronis.com

February 20, 2018 No Comments

[Solved] Set up a Raspberry Pi as a window display (kiosk mode)

Kiosk mode, or running big display to show ads, or company info is a big field in IT.
Sure there are multiple services and companies who will come out and install you a fancy system that you email them to update and all, but what if you just want a low cost, low energy installation that you have full control of?

Well, this was my predicament.

Below is how i set up a Raspberry Pi to run a 4K TV which was then placed on a pole mount in the window of a customers shop. (in fact i have now installed over 13 of these at various locations, all of which require minimal interaction, and are very energy efficient.

The basis is this;
1) Create info/powerpoints/video’s or whatever you wish to display in/on a managed website/url.
2) Have a low powered RPi display that simply boots straight into the website/url of your choice.

The reasons i have chosen this path are many, but the pro’s include, being able to modify and push the content on the fly, without ever having to touch or reconfigure the display or Pi and having the Pi set up in a fool proof way that even if there is a power interruption, the pi automatically reboots and runs where it left off.

Set up a Raspberry Pi as a window display (kiosk mode)

Download Image & Install

Raspbian

Raspbian Latest (Stretch)

Necessary Software for Kiosk Mode
sudo apt-get update sudo apt-get dist-upgrade sudo apt-get install matchbox x11-xserver-utils ttf-mscorefonts-installer xwit sqlite3 libnss3

Then reboot : sudo reboot
Installation of libgcrypt11
wget http://ftp.acc.umu.se/mirror/cdimage/snapshot/Debian/pool/main/libg/libgcrypt11/libgcrypt11_1.5.3-5_armhf.deb sudo dpkg -i libgcrypt11_1.5.3-5_armhf.deb

Installation of Chromium browser 48
sudo apt-get install chromium

# Download ffmpeg extra package
wget http://launchpadlibrarian.net/234969705/chromium-codecs-ffmpeg-extra_48.0.2564.82-0ubuntu0.15.04.1.1193_armhf.deb sudo dpkg -i chromium-codecs-ffmpeg-extra_48.0.2564.82-0ubuntu0.15.04.1.1193_armhf.deb \ Chromium-browser_48.0.2564.82-0ubuntu0.15.04.1.1193_armhf.deb

Configure Chromium Kiosk autostart:

nano .config/lxsession/LXDE-pi/autostart

@lxpanel --profile LXDE-pi @pcmanfm --desktop --profile LXDE-pi @chromium-browser --kiosk --disable-session-crashed-bubble --disable-infobars http://YOUR WEBSITE URL
Hit ctrl+o , ctrl+x

Disable Screen Saver
apt-get install Xscreensaver Set to disable screensaver

Hide Cursor
Get package:
Sudo apt-get install unclutter
Run unclutter:
Unclutter -display :0 -noevents -grab

Resolution Setup:
sudo nano /boot/config.txt

Add in just under: display_rotate=1 (Or “display_rotate=0” for vertical boards)

resolution 82 1920x1080 60Hz 1080p
Or whatever resolution your Video’s/display will be showing

hdmi_ignore_edid=0xa5000080 hdmi_force_hotplug=1 hdmi_boost=7 hdmi_group=2 hdmi_mode=82 hdmi_drive=1

February 2, 2018 No Comments

[Resolved] Find the startup folder in windows 10

Need to find the startup folder in windows 10?

Since Windows 8, the startup folder has been an elusive beast, but fear not, this simple command will force it to reveal itself in no time at all.

1) Win + R
2) shell:startup
3) Enter/OK

find startup folder location win 10 shell:startup

Or the path for the startup folder in windows 10:
"C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup"

startup folder in windows 10

October 3, 2017 No Comments

Powershell Migration Series | Setting bulk forwarding using powershell

Powershell Migration Series

Setting bulk forwarding using powershell

Whilst doing my migration, i want to set up the mailbox so that i can forward any new massages to O365 from the local exchange, after i have done the bulk of mail migration. In order to do this, we utilise the .onmicrosoft.com address space that O365 can provide each email user.

The plan is simple, forward mail from local exchange @contoso.com to O365 @contoso.onmicrosoft.com

Once you have created the contacts, the next step is Setting bulk forwarding using powershell

1) Create another CSV, this time in the following format,

DisplayName,MailAddress

DisplayName = the username in exchange, e.g. “Joe Bloggs”
Mail Address = Forwarding address @contoso.onmicrosoft.com address

Save it as “ForwardingAddresses.csv”

2) Run the following which creates the bulk forwarding using powershell

Import-Csv c:\scripts\ForwardingAddresses.csv | Foreach-Object{Get-Mailbox $_.DisplayName | Set-Mailbox -ForwardingAddress $_.MailAddress}

Now for me, i needed it to deliver to both the exchange mailbox and to forward to the O365 mailbox, if you need it to deliver to the mailbox AND forward, add the below switch to the end of the above before the last curley bracket }

-DeliverToMailboxAndForward $true

Final script i ran:

Import-Csv c:\ws\ForwardingAddresses.csv | Foreach-Object{Get-Mailbox $_.DisplayName | Set-Mailbox -ForwardingAddress $_.MailAddress -DeliverToMailboxAndForward $true}

October 3, 2017 No Comments

Powershell Migration Series | Creating bulk contacts with powershell

Powershell Migration Series

Creating bulk contacts with powershell

Whilst doing my migration, i want to set up the mailbox so that i can foward any new massages to O365 from the local exchange, after i have done the bulk of mail migration. In order to do this, we utilise the .onmicrosoft.com address space that O365 can provide each email user.

The plan is simple, forward mail from local exchange @contoso.com to O365 @contoso.onmicrosoft.com

To do so, on the local exchange there is two steps,

1) create CSV with the following format and your contact data:

Firstname,LastName,ExternalEmailAddress

Save as external_users.csv

2) Run the following which creates the bulk contacts with powershell

Import-Csv “C:\scripts\external_users.csv” | ForEach {New-MailContact -Name $_.Name -Firstname $_.FirstName -LastName $_.LastName -ExternalEmailAddress $_.ExternalEmailAddress -OrganizationalUnit “DOMAIN.local/MyBusiness/Users/SBSUsers/Contacts”}

replace: “DOMAIN.local/MyBusiness/Users/SBSUsers/Contacts” with the OU you wish the contacts to be created in.

You then need to set up the forwarding within exchange, now you have already done the contacts using powershell, why not set forwarding with powershell also?

September 5, 2017 No Comments

Printer fix script – Quickly clear print queues and restart print spooler

printer fix script

Printers are the bain of any helpdesk engineer, or actually any one in IT in general!

Here is a quick printer fix script to help:

Whilst basic, (restart spooler and clear all print queues) it does in our office, at least, clear 99% of printer issues.

Copy and paste the below to a batch file (file extension .bat) and click away:

::Printer Fix Script @cannotdisplay.com
net stop spooler
pause
del /S /F “C:\Windows\System32\spool\PRINTERS\*”
del /S /F “C:\Windows\System32\spool\SERVERS\*”
net start spooler
pause
::end

It will prompt you several times to make sure you wish to delete queues and then pause at the end to show you how it went,
Any alterations or suggestions comment below!

August 28, 2017 No Comments

BGP vulnerable? – is the web as we know it at risk?

The BGP (protocol) has been on my mind the last few weeks.

It boggles my mind how fragile the web is that we all operate on, more specifically that we rely on BGP TCP/IP to maintain connections between two or more autonomous system routers.
BGP is simply put, is the Internet’s greatest weakness.

OK, so what is BGP?

According to he RFC (last pub 2006)

The primary function of a BGP speaking system is to exchange network
reachability information with other BGP systems.

GP-4 provides a set of mechanisms for supporting Classless Inter-
Domain Routing (CIDR) [RFC1518, RFC1519]. These mechanisms include
support for advertising a set of destinations as an IP prefix and
eliminating the concept of network “class” within BGP. BGP-4 also
introduces mechanisms that allow aggregation of routes, including
aggregation of AS paths.

Attacking it?

Acording to Sean Convery (cisco) from his blackhat talk in 2003 below is how you shoudld go about it (kindof, we will go into more detail later):
Reset a single BGP session to control a block of IP’s and corrupt other BGP routers. The easiest way to do this would be to gain lawful access to a BGP backbone, e.g. become an engineer for a site, or befriend someone who has access.

OK, so?

Well from all my readings and research, it seems like this is where the bottom foundational layer of trust the WHOLE internet lies. Without the BGP, there is no CIDR, without CIDR there is no IP’s, without IP’s there is no DNS, without DNS there is no websites, without websites many services simply die and cue end of the world scenarios.

Why was this on my mind? Well i’ve been curious about it before, but recently i have been thinking about the unseen weaknesses in CryptoCurrencies. If the internet breaks, or a government decides to hard fork/cut access and limit it, then crypto as we know it is valueless. It simply looses ALL value.
Crypto other than a few projects all works from HTTP, ip, tor, IPFS etc.. which relies on IP addressing. When the very foundation of these protocols is in question, then the whole behemoth is in danger. BGP simply is the biggest threat to modern crypto economies.

tl;dr: An old protocol (BGP) run by potentially vulnerable companies, could break the internet by issuing bad or malicious commands.

Further reading:
BGP RFC
on wired
Cisco press
techopedia
Network computing.com