November 2018
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November 2018
M T W T F S S
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567891011
12131415161718
19202122232425
2627282930  

iptables tips and tricks

Tip #1: Take a backup of your iptables configuration before you start working on it.

Back up your configuration with the command:

/sbin/iptables-save > /root/iptables-works Tip #2: Even better, include a timestamp in the filename.

Add the timestamp with the command:

/sbin/iptables-save > /root/iptables-works-`date +%F`

You get a file with a name like:

/root/iptables-works-2018-09-11

If […]

SSL and TLS 1.3 on Nginx

I have heard that there is TLS1.3,

I have been tickle, I want to toss and try. In the past, there were not many browsers supported, and there were not many people on the Internet who tried it. There are some large website sites that have already got TLS1.3, and many bloggers have upgraded their […]

tomcat tuning

Sync sync disk

echo 3 > /proc/sys/vm/drop_caches # Clean up useless memory space

Tomcat8 final configuration 1.${tomcat}/bin/catalina.sh Join 1.${tomcat}/bin/catalina.sh JAVA_OPTS=”-Djava.awt.headless=true -Dfile.encoding=UTF-8 -server -Xms1G -Xmx1G -Xss256k -XX:NewSize=1G -XX:MaxNewSize=1G -XX:PermSize=128m -XX:MaxPermSize=128m -XX:+DisableExplicitGC”

2. 2. JAVA_OPTS=”$JAVA_OPTS -server -Xms3G -Xmx3G -Xss256k -XX:PermSize=128m -XX:MaxPermSize=128m -XX:+UseParallelOldGC -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/usr/aaa/dump -XX:+PrintGCDetails -XX:+PrintGCTimeStamps -Xloggc:/usr/tomcat/dump/heap_trace.txt -XX:NewSize=1G -XX:MaxNewSize=1G”

2.${tomcat}/conf/server.xml Open commented out

<Executor name=”tomcatThreadPool” namePrefix=”catalina-exec-” maxThreads=”300″ […]