Same as for Ubuntu 16.04 where systemd is used
I just logged into a root account and followed these instructions…
- My VPS provider (Vultr) allows inserting a public key at the time of a new instance creation, so I created a new key using an existing Linux command line:
ssh-keygen -t rsa
- Name server hostname (I used these instructions (archive) for hostname)
- Set reverse DNS in VPS server console equal to FQDN
- Change SSH port & disable password authentication with
sudo nano "/etc/ssh/sshd_config"then restart ssh
sudo systemctl restart ssh
- create non root user, copy .ssh folder from root to their profile, making sure to
chown newuserfor the authorized_keys file, and add the user to group sudo –
sudo addgroup groupname.
- Add auto security updates.
sudo apt-get install unattended-upgrades
sudo dpkg-reconfigure unattended-upgrades
sudo nano /etc/apt/apt.conf.d/50unattended-upgrades **requires root email for notifications*
- Set time zone
sudo dpkg-reconfigure tzdata
I have a solar pool pump inline with a normal pool filter pump. If the pool pump turns off while the solar pump is on.. then the solar pump can’t pump properly. This is an issue since the filter pump sometimes will turn off in hot weather (or if hot water is flowing through it). I built a sensor to require the filter pump to run in order to run the solar pump. Also I ran an external switch for the solar pump.
I will note that working with mains voltages is inherently dangerous, and I’d advise against it for anyone not sufficiently trained.
The circuit consists of a current sensing board ($5.50 with delivery) and a Zero-Cross SSR ($12 delivered…). The sensor is just a coil around one of the conductors in a ‘sensor’ mains extension cable. When current is high enough through the sensor, the SSR is in turn energised, closing the circuit through a second ‘trigger’ extension cable . I put a switch in between the sense output and the SSR. That’s basically it. I thought about a pull-down resistor on the input for the SSR, but since it needs 5v plus a small current to trigger.. I think it should be fine left open.
Initially I used a current sense board with no relay output, although this did not live up to specs delivering 5v digital output and caused a bunch of issues… eventually I gave up trying to implement a transistor/relay and bought a sense board with an inbuilt relay. The components in the system run off 5v and are powered by a USB power adaptor 🙂
Following this guide.
NOTE 1: In the part where they edit
I edited the server directive to read:
server 192.168.155.0 255.255.255.0
then my UFW rules are
# START OPENVPN RULES Continue reading “OpenVPN Server on Ubuntu 16.04”
# NAT table rules
:POSTROUTING ACCEPT [0:0]
# Allow traffic from OpenVPN client to ens3 (change to the interface you discovered!)
-A POSTROUTING -s 192.168.155.0/24 -o ens3 -j MASQUERADE
# END OPENVPN RULES
So the banana plugs on the back of my sub failed/the plastic back plate melted when I used the sub as a wind break. I decided to re-do the connection using really good Neutrik Speakon connectors.
It’s been too long since I put some time into this project, so I’m going to outline goals broadly and then narrow into smaller components.
- Enumerate SIM software options, noting:
-DK2 compatibility, Retail rift (CV1) compatibility (which has many moderate advantages over DK2), environmental data output capabilities, associated existing environmental data hardware.
- Enumerate environmental data hardware options. Most all options are for motion platforms, will these work for my full 3D system?
- Options for motion actuation, look into various high torque motor options. Variables include torque, rotation accuracy, rotation speed, control interface and compatibility with environmental data hardware.
- Physical design. Design different styles, noting size requirements, mass, portability, aesthetics, structural design and stress tolerance calculations. Construction may need some legal/insurance considerations.
Steps 1-3 represent the bulk of the electronic challenges. Step 4 is the physical challenge Continue reading “SAP – refocusing”
In Ubuntu 16.04 DNSCrypt can be installed from apt-get:
sudo apt-get install dnscrypt-proxy
Assuming a wireless interface is setup and working on the router, we can add a virtual interface, give it it’s own subnet, and isolate that subnet from the existing LAN. Note: these routers don’t seem to like multi-tasking/wi-fi too much Continue reading “isolated wifi using a Mikrotik wireless router”