How to Generate SSH/SSL Public and Private Keys

By: Kevin | December 6, 2016


  1. ssh-keygen -t rsa -b 2048 -f keyName
    Tap enter twice to skip the passphrase, or enter one if you like.
    This will output keyName and

SSL with self-signed Certificate Authority (CA)

  1. Create CA key without passphrase openssl genrsa -out rootCA.key 2048 add -des3 if you want a passphrase
  2. Self sign the CA, openssl req -x509 -new -nodes -key rootCA.key -sha256 -days 1024 -out rootCA.pem. Now you have a self signed SSL named rootCA.pem


Use the CA just created to sign other SSL certificates.
  1. Create a private key, openssl genrsa -out device.key 2048
  2. Create a certificate signing request (CSR), openssl req -new -key device.key -out device.csr. Its important to note when answering the prompts, Common Name (eg, YOUR name) []: must match the host name of the web server you are using.
  3. Sign the CSR with your CA.openssl x509 -req -in device.csr -CA rootCA.pem -CAkey rootCA.key -CAcreateserial -out device.crt -days 500 -sha256

Handy Linux commands

By: Kevin | August 22, 2016

Handy Commands to remember:


Recursively Change permissions

sudo find /var/log/test -type f -exec chmod 777 {} \;

sudo find /var/log/test -type d -exec chmod 777 {} \;


Search multiple files:

find . -name "*.log" | xargs grep -i <something>

grep -B x -A x file.log


Snapshot Date

date -u +%Y/%m/%d-%H:%M


Linux Permissions Cheat Sheet




4 read (r)

2 write (w)

1 execute (x)

7 = 4+2+1 (read/write/execute)

6 = 4+2 (read/write)

5 = 4+1 (read/execute)

4 = 4 (read)

3 = 2+1 (write/execute)

2 = 2 (write)

1 = 1 (execute)

Notes to self about WinRM

By: Kevin | August 22, 2016

Notes to self about WinRM.

On WinRs (client side) box, need to add ‘TrustHost’ to use CLI
winrm set winrm/config/client '@{TrustedHosts="machineA,machineB"}'

Trust all
winrm set winrm/config/client '@{TrustedHosts=“*”}’

List WinRm Listener IP and Port
Winrm enumerate winrm/config/listener
winrm e winrm/config/listener




Check running services

net start


Stopping and removing all Docker containers at once

By: Kevin | July 27, 2016

I found myself getting tired of copy and pasting UUID’s to remove containers one by one. I found this little snippet to help speed things up.

Stop all containers:
docker stop $(docker ps -a -q)

Remove all containers:
docker rm $(docker ps -a -q)


By: Kevin | July 2, 2016

Using brew on OS X,

To install:
brew install mysql

To start the server:
mysql.server start

To stop the server:
mysql.server stop

Monthly Update – 6/27/16

By: Kevin | June 27, 2016

I’ve essentially let the tank go the past 3 months and have only added top off water as needed. Surprisingly thing are going great.

  1. 5 gallon water change.
  2. Plant has been growing nicely.
  3. 4 Cardinal Tetras are all healthy
  4. Phosphates are through the roof however everything else is normal.

"IMG_4084 IMG_4083

How to add or edit cronjobs

By: Kevin | June 27, 2016

Note to self:

Perhaps use sudo.

To list jobs:

crontab -l


To edit jobs:

crontab -e

Monthly Update – 3/10/16

By: Kevin | March 10, 2016

Depressing changes since last update:

  1. Tank die off, 17 Cardinals down to 4. Pelco died.
  2. pH has been creeping >7.5 so I’ve added some chemicals to bring it down. I also added a piece of drift wood. The day after adding the wood my pelco was dead so I took it back out.
  3. 15% water change, used tap water conditioner and Proper pH 6.5
  4. New filter
  5. New carbon
  6. Got a new Pelco.

Everything is near zero except Phosphates, which are through the roof! Which explains why the tank has had an algae bloom.


Got new lighting! 🙂

Weekly Update – 2/5/2016

By: Kevin | February 5, 2016

Since last post:

  1. 15% water change
  2. Vacuumed gravel
  3. New carbon
  4. New filter
  5. 17 more Cardinal Tetras, yes 17

Everything is around 0.


Weekly Update – 1/24/2016

By: Kevin | January 24, 2016

Since last update:

  1. Water top offs to account for evaporation.

Measurements have really stabilized. ph ~7.6, Ammonia ~0, Nitrite ~0, Nitrate ~0, and new for this post Phosphates which appear to be off the charts.


The water looks crystal clear. But if you look closely algae is on the rocks and all over my fake plant and the back wall.


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