“We in this country are facing a lack of visionary servant leadership. Any leader you can think of will say they are fighting for people, and this is a necessary but insufficient condition for being a leader, to fight for people that need you. But what we really need for real vision is level two and level three servant leadership. What’s level two servant leadership? It’s fighting for people that need you that you don’t need. Level three servant leadership is fighting for people who don’t like you. This is the problem, where we split into tribes where leaders only lead their followers.” Arthur Brooks, February 18, 2016, TED 2016, Vancouver, British Columbia
Miki Agrawal on perseverence
It takes 10 years to be an overnight success
Quote from a talk by Herschel Walker at Copart’s annual Global Leadership conference
“To get there you have to work
To stay there you still have to work”
Over the last week, I moved this blog from a LAMP (Linux, Apache, MySQL, PHP) stack to LEMP (Linux, Nginx, MySQL, PHP) stack. Have a blog post in the works with all the gory details, but wanted to quick document a quirk in the WordPress + Nginx combination that broke permalinks on this site.
Permalinks are user friendly permanent static URLs for a blog post. So for example this particular blog post’ URL is
This works by default in Apache because WordPress puts in the required rewrite rules.
To get it work in Nginx, you have to add the following config in the Nginx site configuration
Under the / location context, add the following
try_files $uri $uri/ /index.php?$args;
This is essentially telling Nginx to try to display the URI as is, and if it fails that, pass the URI as an argument to index.php.
We ran into an issue at work recently, when trying to deploy a spring boot based micro service. The application included some libraries that were downloaded by the application using maven during runtime.
The environment that this application was running in had controlled access to the Internet. We configured the jvm parameters using the following parameters
-Dhttp.useProxy=true -Dhttp.proxyHost=PROXY_SERVER_NAME -Dhttp.proxyPort=xxxx
when running the application, we were getting failed dependency errors that stated something like this
Caused by: org.eclipse.aether.resolution.ArtifactResolutionException: Could not transfer artifact com.xxxxx.boot:xxxx -boot-autoconfigure:pom:0.0.1-SNAPSHOT from/to central (http://repo1.maven.org/maven2/): Connection refused at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:444) at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:246) at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:223) at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:334)
Lot of head scratching, because the server running the application had connection to the proxy server and the JVM parameters were accurate.
Finally, we figured out Maven doesn’t use the JVM startup parameters and had to have proxy access configured specifically. There are two ways to do this
- Add an environment variable called “MAVEN_OPTS” and pass the proxy server settings.. something like this
set MAVEN_OPTS= -Dhttp.proxyHost=PROXY_SERVER_NAME -Dhttp.proxyPort=xxxx
- Configure the proxy server settings in Maven’s settings.xml… something like this
<proxies> <proxy> <id>genproxy</id> <active>true</active> <protocol>http</protocol> <!--username>proxyuser</username--> <!--password>proxypass</password--> <host>myproxy.mycompany.com</host> <port>8080</port> <nonProxyHosts>*.mycompany.com|127.0.0.1</nonProxyHosts> </proxy> </proxies>
Command parameters for varnishlog to view the backend server that is processing the request. In this particular case, I wanted to see the request URL and backend server for any responses with HTTP code 401 (unauthorized access)
sudo varnishlog -i BackendOpen,BereqURL -q "BerespStatus == 401"
Found this good article by Mark Huot regarding using curl to check websocket servers at http://www.thenerdary.net/post/24889968081/debugging-websockets-with-curl
curl -i -N -H "Connection: Upgrade" -H "Upgrade: websocket" -H "Host: echo.websocket.org" -H "Origin: http://www.websocket.org" http://echo.websocket.org
On a server that is running either the FTP client on server, you can capture the ftp password using tcpdump by
tcpdump -A port ftp
I learned today that “laser” is an acronym that stands for light … amplification by … stimulated … emission of … radiation.
Who knew? 🙂