How to purge the cache of a page
I get sometimes requests from customers to invalidate the cache for a particular webpage only. From inside the server the PURGE request is allowed so: curl –insecure -I…
Regexp hints
echo "bla bla word word1 = string1 string2" | sed -e 's/.* \([^ ]*\)=.*/\1/g' Some basic regexp hints: the first /…/ is what your string should match s…
Checking the Validity Date of an SSL Certificate
echo | openssl s_client -connect maven.escenic.com:443 2>/dev/null | openssl x509 -noout -dates
How to restart network interface
ifdown eth0 ifup eth0
How can I monitor the memory usage?
watch -n 5 free -m
Default max heap size
If you need to get the default max heap size used by your machine: java -XX:+PrintFlagsFinal -version 2>&1 | grep MaxHeapSize
How to convert the ^M linebreak to ‘normal’ linebreak in a file opened in vim?
:%s/<Ctrl-V><Ctrl-M>/\r/g Where means type Ctrl+V then Ctrl+M. Explanation :%s substitute, % = all lines <Ctrl-V><Ctrl-M> ^M characters (the Ctrl-V is a Vim way of writing the Ctrl ^…
find difference between two text files with one item per line
grep -Fxvf file1 file2 Where -F, –fixed-strings Interpret PATTERN as a list of fixed strings, separated by newlines, any of which is to be matched. -x, –line-regexp Select…
how to extract the first and the last x lines of a big file
If you are debugging big txt files, i.e. 6G+, a good start is to check what is at the top and at the end of it. export file=/Users/racoonlab/Downloads/engine.out;…
Find a particular request and its relative url
If you need to find the url that serves a particular requests, i.e.: 400, you can try running this on the varnish server: varnishlog -i RxURL,TxStatus | tee…