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Apache configuration

SSL certificates

CNAME domain name validation

Memcached

Command results redirection

Apache configuration

$apachectl -M = check enabled modules

$sudo nano /etc/apache2/mods-available/mpm_event.conf = increase apache inbound concurrent connections to 5000

ServerLimit 250

StartServers 10

MinSpareThreads 75

MaxSpareThreads 250

ThreadLimit 64

ThreadsPerChild 32

MaxRequestWorkers 8000

MaxConnectionsPerChild 10000

</IfModule>

SSL certificates

Create csr and private key on ubuntu:

openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr

https://www.namecheap.com/support/knowledgebase/article.aspx/9446/14/generating-csr-on-apache-opensslmodsslnginx-heroku/#3

CNAME domain name validation

- Create DNS record and delete domainname.com from host but leave a "." at the end

- Leave .comodoca.com but add a "." at the end of text box "Points"

- Go to mxtoolbox and do a CNAME lookup for your domain to see if it was published or not

Memcached

$sudo apt-get update

$sudo apt-get install memcached

$ps aux | grep memcached = find memcached running process, port, IP and username

$ /usr/share/memcached/scripts/memcached-tool 127.0.0.1:11211 stats = check if memcached get any hits and does his job

$echo stats | nc 127.0.0.1 11211 = check memcached parameters and status/functionality

$echo "stats" | nc -w 1 localhost 11211 | awk '$2 == "bytes" { print $2" "$3 }' = check memcached size

Command results redirection

To write the output of a command to a file, there are basically 10 commonly used ways.

Overview:

List:

• command > output.txt

The standard output stream will be redirected to the file only, it will not be visible in the terminal. If the file already exists, it gets overwritten.

• command >> output.txt

The standard output stream will be redirected to the file only, it will not be visible in the terminal. If the file already exists, the new data will get appended to the end of the file.

• command 2> output.txt

The standard error stream will be redirected to the file only, it will not be visible in the terminal. If the file already exists, it gets overwritten.

• command 2>> output.txt

The standard error stream will be redirected to the file only, it will not be visible in the terminal. If the file already exists, the new data will get appended to the end of the file.

• command &> output.txt

Both the standard output and standard error stream will be redirected to the file only, nothing will be visible in the terminal. If the file already exists, it gets overwritten.

• command &>> output.txt

Both the standard output and standard error stream will be redirected to the file only, nothing will be visible in the terminal. If the file already exists, the new data will get appended to the end of the file..

• command | tee output.txt

The standard output stream will be copied to the file, it will still be visible in the terminal. If the file already exists, it gets overwritten.

• command | tee -a output.txt

The standard output stream will be copied to the file, it will still be visible in the terminal. If the file already exists, the new data will get appended to the end of the file.

• (*)

Bash has no shorthand syntax that allows piping only StdErr to a second command, which would be needed here in combination with tee again to complete the table. If you really need something like that, please look at "How to pipe stderr, and not stdout?" on Stack Overflow for some ways how this can be done e.g. by swapping streams or using process substitution.

• command |& tee output.txt

Both the standard output and standard error streams will be copied to the file while still being visible in the terminal. If the file already exists, it gets overwritten.

• command |& tee -a output.txt

Both the standard output and standard error streams will be copied to the file while still being visible in the terminal. If the file already exists, the new data will get appended to the end of the file.

https://askubuntu.com/questions/420981/how-do-i-save-terminal-output-to-a-file

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