Solving DKIM verification FAILED with Bad Format in Gmail email messages

DKIM (Domain keys identified Mail) is a scheme for which allows a receiver to verify that the email originated (or authorized) by the domain’s owner via a digital signature.

Having DKIM signature adds credibility to the email messages sent from the origin host/domain, which is crucial for automated emailing system to avoid the messages from being suspected as SPAM email or spoofed email.

I managed to set up DKIM for an academic journal website which I’ve managed. The journal’s runs on Open Journal System web application, the addition of DKIM is crucial to avoid GMail or Microsoft Live from labeling the automated emails sent from the academic journal from being labeled as spam.

At first I found that the DKIM scheme that I’ve setup was running fine and the email messages was verified correctly from my Organizational email domain. However, I’ve noticed a problem when the automated email sent from OJS is not properly verified by Gmail-addressed account (@gmail.com). Upon inspection in the email header, I’ve noticed that the GMail marked the DKIM signature sent from my domain as “bad format”. Example below:

DKIM:	'FAIL' with domain jcrinn.com

dkim=neutral (bad format) header.i=@example.com header.s=mail header.b=AbCdE5g;

After hours of searching and debugging, including referring to the DKIM NS TXT record for reference, I finally found out that Gmail treat the “g=*” optional parameter as required, and thus I’ve to append “;g=*” to the DKIM TXT record on my domains’ DNS record.

So it become similar like this:

TXT default._domainkey  v=DKIM1; p=yourPublicKeywHiCHi5+abit+1OnG; g=*

After altering the records, it seems GMAIL finally able to verify the automated emails sent from my OJS-based web application

The “signed-by” is visible when DKIM is successfully validated by GMail

Hopefully this will work out fine for you too!

P/S: DigitalOcean has an excellent tutorial on DKIM installation and setup in GNU/Linux operating system.

How to convert character encoding in text files

Here is how to convert text files from one character encoding to another in GNU/Linux:

#eg1
iconv -f ASCII -t UTF-8//IGNORE file.txt -o output.txt

#eg 2
iconv -f ISO-8859-1 -t UTF-8//TRANSLIT file.txt output.txt

The -f parameter denotes “from” and -t parameter denotes “to” character set.
//IGNORE means the “iconv” will ignore any characters that are not available in the target character set.

While “//TRANSLIT” means the converter will attempt to substitute characters that are not available in the target character set to the closest characters available, failing that, “???” will be replaced in its place.

Most GNU/Linux distribution have iconv preinstalled, if not, please consult your distribution documentation.

No time to read lengthy articles? TLDR Chrome extension will digest that for you

Ever encountered long winded article which makes you feel like you do not want to read?

Enter TLDR; Chrome extension, a browser extension made by Recognant which can summarize any article for you.  The extension works well with English language article, but upon my inspection, it can also works well for Malay language article.

A must have extension  for those who just want to browse through articles at a glance.

Digitalocean upgraded their Droplets hosting Offering

Good news for those looking for VPS hosting solution. Digitalocean has upgraded their droplet offering by increasing the diskpace and RAM at the same price point.

Here are the new Droplets package from Digitalocean:

The most interesting plan is Flexible droplets where you can resize the droplets at any time choosing between with RAM or vCPU at the same price point.

Benefit for existing customer:

Existing customer can enjoy the new price point by clicking “Resize” option to get the new offering from Digitalocean

Benefit for new customers:

New customer will enjoy USD10 giveaway when signing up with Digitalocean. Remember that Digitalocean charges by hour, so you can test drive their VPS in a few days and can decide whether you want to continue or not with their service without any penalty

How to convert Microsoft Office *.docx files to PDF using Linux in command-line

Here’s how to convert Microsoft Office *.docx files to PDF using Linux in Command Line.
This trick can also be used together with other documents files supported by LibreOffice

First make sure you’ve installed the latest version of LibreOffice for use in command line environment.
Assuming the user is ‘example’ and the filename to convert is ‘doc.pdf’.

libreoffice --headless -convert-to pdf --outdir /home/example/ /home/example/doc.docx

The conversion can also be adapted to PHP or Python using their respective shell_exec or subprocess directive.