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  It looks like TechCrunch blocks GoDaddy server access

Recently, I encountered an issue with an app I maintain—it suddenly stopped pulling RSS feeds from TechCrunch. At first, I suspected that the RSS feed URL might have changed. However, after further investigation, I discovered a different story. The URL itself was unchanged, but the results varied depending on where the request was coming from. To troubleshoot, I started by setting up a local web server and running a test with my script to see if it could still pull the RSS feed. The script...

   TECH CRUNCH,GODADDY,AI,BLOCK ACCESS     2024-08-17 12:31:52

  Solving easy problems the hard way

There’s a charming little brain teaser that’s going around the Interwebs. It’s got various forms, but they all look something like this: This problem can be solved by pre-school children in 5-10 minutes, by programer – in 1 hour, by people with higher education … well, check it yourself!  8809=6 7111=0 2172=0 6666=4 1111=0 3213=0 7662=2 9313=1 0000=4 2222=0 3333=0 5555=0 8193=3 8096=5 7777=0 9999=4 7756=1 6855=3 9881=5 5531=0 2581=? SPOILER AL...

   Problem solving     2012-04-05 23:40:35

  Python FTP Server and Client

Distributed Log File Automated Archive System This week, we will introduce the automated compute cluster nodes' log automated archive system project and FTP Communication utility library module. Program Design Purpose: This project aims to create an FTP server & client lib program for file transfer and a files management system for log data synchronization. We will develop an automated log file archive system that regularly collects newly generated log files from multiple nodes in a compute...

       2024-09-29 04:07:50

  Let's talk about JavaScript deep clone

In JavaScript, deep clone means creating a brand new object that includes all nested objects, with all properties being completely independent copies. This is different from shallow copying, which only copies the first-level properties, with nested objects being referenced rather than copied. There are multiple ways to perform deep copying in JavaScript, but the best one to use depends on the specific use case. Can use JSON.parse & JSON.stringify? ❌ JSON.parse(JSON.stringify(obj)) is a dep...

   JAVASCRIPT,DEEP CLONE     2023-02-25 08:57:11

  Google to build Google Babble to unify all its chat tools

--Note : Image is from www.36kr.com If Google Talk / Hangout / Voice / Messenger are put  together, what will you find?They are all chat tools launched by Google, but with careful comparison, you will find that the difference between them is not very big. The useful tools are Google Talk and Google+, but both of them needs to be improve their user experience.According to Geek.com, Google is planning to launch a chat application Google Babble which will integrate all its chat tools and serv...

   Google Babble,Chat tool     2013-03-19 13:02:47

  WireGuard VPN Troubleshooting

When you are working as a network/cluster admin for you team to config the WireGuard VPN for other members, you may meet some of the problems below and these are the solution you can try to fix them. ----------------------------------------------------------------------------------------------------------- Problem [1]: The WireGuard handshake request send from the client can be received from the server but the server's response was blocked at some where so the client can not receive serv...

   WIREGUARD,VPN,TROUBLESHOOTING     2021-12-14 09:17:46

  bash network interface

Some of us may have seen /dev/tcp/<host>/<port> before, is this a special file system implemented in some BSD kernel? Because there is no /dev/tcp in Linux. Actually, this one is implemented in bash. We no need to rely on wget,nc to do network connection. It's very easy to use this interface: bash-4.2$ cat </dev/tcp/time.nist.gov/13 56188 12-09-18 15:34:26 50 0 0 733.5 UTC(NIST) * bash-4.2$ exec 3<>/dev/tcp/www.w3.org/80 bash-4.2$ echo -e "GET / HTTP/1.0\n\n" >&3 b...

   Bash,Network interface,/dev/tcp     2013-07-20 00:57:52

  6 time management tips for startups

Many people are fighting for their startups, they are willing to put all their time in company operations. This 24x7 passion is necessary for startup founders. For the team in startups, the most important thing is time management, time management is a top challenge for everyentrepreneur. After years of experience working with entrepreneurs and business owners, Rieva Lesonsky has  learned a few tricks for getting more done in the 24 hours we all have. Here are 6 tips what he shared...

   startup,time management     2012-05-29 05:30:07

  Why you should be careful about optimizations

In one of my current javascript projects, I have to deal with 3D voxel coordinates. And, sometimes, I have floating points coordinates which must be converted to integers in order to convert them into proper array index. Javascript is a wonderful language, really. However, implementations are sometimes weird, and the way to do something can sometimes have very huge impacts on the performances. Worse, sometimes the classical way is more expensive than the tricky one. So, some peo...

   JavaScript,Bitwise,Floor,Trick,Optimization     2012-05-02 11:29:20

  The Pitfall of WebSocket Disconnections Caused by Browser Power-Saving Mechanisms

Preface Recently, while using WebSocket (WS) connections, we encountered frequent disconnection issues, occurring hundreds of times per day for a single user. Although using the auto-reconnect feature of socket.io allowed us to quickly restore connections after disconnections, it did not guarantee that every reconnection would successfully receive WS messages. Therefore, we conducted several investigations and tests. Ultimately, we identified the root cause of the issue: the browser's power-savi...

   WEBSOCKET,JAVASCRIPT,POWER SAVING,TROUBLESHOOTING     2024-06-23 01:19:39