Tag: network

Posted on

Changing DNS Servers with NetworkManager

I’ve never used network manager before, and right now I have a need to change the DNS settings on a system of mine that just so happens to be using it. Let’s look at the commands to change the DNS servers using network manager.

To modify the DNS server settings, we’ll want to call the network manager CLI modify connection and input the DNS settings we want to change. For the terminal, this becomes “nmcli con mod”. We then give it the connection name, “ipv4.dns” argument, and a list of the DNS servers to set. The full command can be seen below.

nmcli con mod $connectionName ipv4.dns "8.8.8.8 8.8.4.4"

connectionName can be found by command: nmcli con. In the question case, it will be "System eth0"as always, after configuration changes, restart the service

As always, after configuration changes, restart the service

service NetworkManager restart

Now we should have our new DNS servers active for our network configuration.

Resources

Posted on

Network Layout

Here is a rough guide of how I have my network laid out. I haven’t really documented it before, so hopefully this covers the major points. I use a number of VLANS in my network to keep the IOT devices from being security threats, and prevent security devices from being able to access the internet (like security cameras).

I will write up a longer guide later on when I have some time, for now the short of it. The hardware is mostly Unifi gear with a Unifi controller running on my Proxmox host. This is the same host I run home assistant on (all virtual machines). The Unifi controller lets me configure my whole network in one pane of glass, its a bit of a pain at times, but for me the convenience has outweighed the higher price and limitations so far.

Continue reading “Network Layout”
Posted on

Fixing network problems in HASS

Recently I have been working on fixing the configuration issues in my home assistant installation. I run the supervised mode on an Ubuntu VM that I setup myself with some scripts (since it’s not supported by the official installer). Due to this, I encountered a problem with network manager in home assistant that caused home assistant to lose Internet access (so unable to download updates) even though the VM has no problems accessing the Internet as a whole.

Continue reading “Fixing network problems in HASS”
Posted on

The VLANs Strike Back

I recently re-did my entire network, changing out switch locations, what ports were plugged into where, and so on. This wasn’t too bad, except I didn’t make note of one thing: which ports were VLAN tagged. This became quite the struggle as I tried to figure out why my WiFi couldn’t access the internet, and why all my servers were inaccessible. I even changed what port the Unifi AP was plugged into to try and kick that VLAN possibility out of the running. Little did I know that BOTH ports I tried to plug the AP into were tagged, so neither could reach the internet. I ended up plugging my RT-N16 back into the modem to see that I had internet, and then moved the switch port the access point was into one more time to find a port that wasn’t tagged. Once I had that, I swapped what port my servers were plugged into to find a non-tagged port, that would get my Unifi controller back up so I could go and clean up the rest and get things back into an operational state.

TLDR: Label or remove VLANs before re-architecting things

Posted on

MDNS Across Unifi VLANs

I started working on some hardware projects related to home assistant using the ESP8266. in working on these I learned that the ESP devices use mDNS to advertise their hostnames for communicating with them. My devices however are on a separate VLAN that’s unable to communicate with the internet, and that VLAN was also blocking the mDNS updates from making it through to home assistant, keeping it from being able to know the hostnames. I could use static IPs for this, however I want to avoid locking all my little smart devices to static IPs.

Continue reading “MDNS Across Unifi VLANs”
Posted on

Network Rack Upgrade

I recently needed to build out a new network. The new network had a box in place that I could use for gear, however that box wasn’t big enough for any rack mount gear. I decided to mount a rack over the top of the box to handle all of the gear and keep it organized. With the new network, also came with a need to expand the number of switch ports I have available. I set it up to drive POE to all the end points so that I could have better centralized power.

Continue reading “Network Rack Upgrade”
Posted on

Upgrading Ubuntu Host for Unifi Controller

My unifi controller was installed on an Ubuntu server back on 16.04 LTS. This server finally reached end of life and I needed to run an upgrade to Ubuntu 20.04 LTS. I decided to first try to just release upgrade it two steps. I’d tried this in the past and failed which is why it stayed out of date for so long, but maybe the upgrade process was fixed for things to work automagically. I was a bit wrong on that, however I also found out that rebuilding from scratch is pretty easy.

Continue reading “Upgrading Ubuntu Host for Unifi Controller”