Troubleshooting HTTP 503 Issues

 I have mentioned in the past that you should really look ‘under the hood’ as far as application communication goes.

I have seen many web applications that ‘work’ but not ‘work well’. if you dig in, you may find error messages or logs. Errors can caused many different ways;

• Application - Messages are entirely application based and are addressed by the application team or vendor.
• Sending commands with no authentication, wait for the error message, then resend the same command but this time with authentication
• Using small packet or data payload sizes
• Inefficient multi-tiered server architecture
• Login processes that constantly download application files without checking if you have them already 
• References to servers that are de-commissioned or only used for testing/development
• Network – Messages generated by the network devices that can affect application performance and are addressed by the networking team, like ICMP redirects
• MTU issues caused by different network topologies, firewalls, routers or load balancers
• Blocked ICMP error messages that the application needs to make proper adjustments, like MTU and routing

The Meaning of Old

Most of us grasp the meaning of “old” but putting it into words can be challenging. When it comes to people who might be old, there are plenty of euphemisms to choose from. Senior, elderly and senior citizen come to mind, while terms like curmudgeon or geezer are available when appropriate. According to Webster’s, old is something that dates from the distant past, is distinctly different from something similar of an earlier date, has existed for a specified period of time, is advanced in years or shows characteristics of age. Old, it seems, is relative.

Baselining, No Problem

Not a week goes by without an email from someone asking me to how to create a baseline or worse, requests to review their baseline. I will explain both points before moving on.

Asking how to create a baseline

Spoiler alert, there is no real baseline ‘standard’ or ‘template’ that will meet all your needs. Of course there are typical things that you always document, but after that, it gets very specific. Everyone will use the same software differently.

A great example is Microsoft Outlook, a sales person will use the contacts like a CRM with conversation notes and follow up dates, where an IT person will use the same contacts feature to simply record contact info.

This is precisely why I usually ask the I.T. specialist to spend a little bit of time with the user to determine how they use the software, basic tasks, etc before capturing packets.

Requests to review a baseline

So You Want To Be A ...

 

As the prospect of retirement begins to appear on the outer edges of my radar, I’ve been reflecting on this engineering career that has occupied a large chunk of my adult life. It’s been a rewarding journey and I have no regrets, but what was it that excited me about engineering in the first place?

I don’t believe it was genetics; my Dad was a Professor of Speech and Drama, and my Mom was a schoolteacher who chose to stay at home once I was born. I don’t recall lying in my crib staring at some dangling toy and thinking “I can do better than that.” It’s safe to conclude that I wasn’t born for this profession. If not nature, it must have been nurture.

Finally! It's easy to capture long term.

"Long term packet capture" and "ease of use" are concepts that rarely go in the same sentence.

Usually, long term packet capture means one of two things. 1) Buy a glitzy, massively expensive, petabyte capture solution that streams a zillion bits per second to disk. 2) Use Wireshark or tshark to do a rolling capture buffer that captures a bunch of files with a dizzying amount of detail.

And then - there was IOTA.

Plug in, power up, press capture. Done.