networking [Paul's Wiki]

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Added the diskstation to the hosts. Named it disksta /etc/hosts/

To upload an ssh key to a server: ssh user@hostname 'cat >> .ssh/authorized_keys' }

To cat a file contents to the sytem clipboard: xclip -selection clipboard }

To get ssh-add automatically setup: karlcode.owtelse.com/blog/2015/06/27/passwordless-ssh-on-synology/

To disable a network adapter. sudo_ip_link_set_down_enp0s31f6}

To enable a network apadter: sudo_ip_link_set_up_enp0s31f6}

1. Find the following information using ifconfig and ethtool: - MAC Address: 50:7b:9d:f0:bf:3c - IP Address: 192.168.1.14 - Network Address: This is some thing you can calcated using the mask - Simplex, half or full - full - Speed 1000

Some commands we used:

This gives us statistics. ethtool_-s_eth0}

This changes the speed of our port! The duplex command needs to be sent in also ethtool_-s_eth0_speed_100_duplex_full}

Statistics on your network: netstat_-s}

How does my computer discover the hardware address of other computers. Theres a protocol that happens in the background, called address resolution protocol that find the hardware address based on the ip.

Use the arp command.

We want to see who is currently connected to us: netstat_-t}

To get a feel of what ports are in use read the file: /etc/services

netstat -r shows the routing table.

= Name Resolution =

Ok, cool, I'm finding shit with this. https://community.netgear.com/t5/Wireless-N-Routers/Can-t-access-local-hosts-by-name/td-p/1032440

Avahi, is a name resolution service that broadcasts out the name of the machine. It is automatically installed in ubuntu and to use it you have to just apped .local to the end of the hostname. You can try this also:

avahi-resolve -n dev-laptop.local

Ok so this is a complicated thing. To resolve over my openvpn, its gonna be equal pain in the dick. So, if i'm at the shop, just export the ROS_MASTER_URI to dev-laptop.local and td1.local and if i'm over vpn, use the ips. Easy peasy.

= Wireless = To look at link information: nmcli dev wifi