A Technical I.T./DevOps Blog
Question
You want to know discretely what the third way of the three-way handshake is in the context of TCP/IP networking. What is it?
Short Answer
It is the sending of a TCP packet with a flag of “ACK” from the client to the server/destination.
Longer Answer
The third way is sending a TCP packet with the “ACK” flag (of which several potential flags are possible) to the destination:
Client —–>
…
Continue reading “What Is The Third Way of the Three-Way Handshake?”
Question
You want to know discretely what the second way of the three-way handshake is in the context of TCP/IP networking. What is it?
Short Answer
It is the sending of a TCP packet with a flag of “SYN-ACK” from the server/destination to the initiating client (after the first way was completed).
Longer Answer
The second way is sending a TCP packet with the “SYN-ACK” flag (of which several potential flags are possible) to the destination:
Server —–>
…
Continue reading “What Is The Second Way of the Three-Way Handshake?”
Question
You want to know discretely what the first way of the three-way handshake is in the context of TCP/IP networking. What is it?
Short Answer
It is the sending of a TCP packet with a flag of “SYN” from the client to the server/destination.
Longer Answer
TCP is used in HTTP communications. TCP uses a three-way handshake;
…
Continue reading “What Is The First Way of The Three-Way Handshake?”
Question
You are not familiar with this example of a colon. It appears to be an assignment of a value to itself. You have seen Python function signatures with colons to explain the data type. You have seen colons to signify an if conditional or a for loop. You are not sure what this line of code does:
new_var = a[i:i + counter]
What does this type of colon syntax mean?
…
Problem scenario
You want to use Python to calculate the latest price of various cryptocurrencies. What should you do?
Solution
Prerequisite
This assumes you have installed pip.
Procedures
Install the Python package cryptocompare: pip install cryptocompare
Run this program:
import cryptocompare
print(cryptocompare.get_price(‘BTC’, ‘USD’))
print(cryptocompare.get_price(‘BTC’, ‘USD’))
print(cryptocompare.get_price(‘ETH’, ‘USD’))
print(cryptocompare.get_price(‘LTC’, ‘USD’))
print(cryptocompare.get_price(‘XRP’, ‘USD’))
If you want to receive free cryptocurrency by just learning more,
…
Problem scenario #1
You just installed Linux on a new VM. You boot up your Debian distribution of Linux (e.g., running via Oracle VirtualBox). You see at the login prompt, “cloud-init…running modules:config…DataSourceNone…cc_final_message.py[WARNING]: Used fallback datasource”. What should you do?
Problem scenario #2
You recently created a new server. When you boot your Debian/Ubuntu/Mint server, it seems to hang with an error message about “cloud-init cc_final_message_py [warning]: used fallback datasource.” What should you do?
…
Continue reading “How Do You Solve the Login Prompt Message “Cloud-init…modules:final…Datasource”?”
Problem scenario
You want to have a release. You are concerned that if new code changes are made to the main branch of the relevant repository that the upcoming production release will have a problem. You are not sure if you should allow changes to take place or if should you have a code freeze. Is it a best/recommended practice to have a code freeze going into the release weekend?
…
Continue reading “Is It a Recommended/Best Practice to Have a Code Freeze?”
Problem scenario
You read that it was usually a best practice to check code in daily or more frequently to the main branch. Is this always true?
Solution
No, it is not always true. It is advisable to check code in regularly, but you cannot always check code in this frequently.
In some situations a developer would be terminated for checking in code daily.
…
Continue reading “Is It a Best/Recommended Practice to Check Code in Frequently?”
While some people recommend you purchase a wallet, if you do not mind storing your crypto on a third party platform, you could earn interest.
Some of the advertised rates are above 5%. The cryptocurrency is not backed by FDIC. To learn more about how it works, see these postings:
If you want to receive free cryptocurrency by just learning more,
…
Problem scenario
You have installed the Amazon Workspaces Client on your Ubuntu or Linux Mint server. You want to start the application from the GUI desktop. What do you do?
Possible solution #1
Run this command: sudo find / -name workspacesclient*
Possible solution #2
Try running this from the terminal:
/opt/workspacesclient/workspacesclient
…
Continue reading “How Do You Launch the Amazon Workspaces Client from Your Debian Server?”