Author Topic: Trying to Understand Network  (Read 1081 times)

Trying to Understand Network
« on: 09 September, 2018, 11:11:16 am »
I have a router, with a laptop and a mini desktop connected via ethernet, which is in turn connected through TPLink mains plug-in devices (a main one connected directly to the router (also TPLink) and 3 slave units. This all seems to work fine.  On one LPLink device, I also have an all-in-one printer (HP OfficeJet 6310) connected both via USB and via ethernet.

Now that I’m using Debian stretch, I’m getting to know the ip command, rather than the old ifconfig command under jessie.  However, it’s all a bit cryptic for me!  I ran the commands below with laptop turned off, the mini desktop running, and the printer on but, according to CUPS (I’ll come to this later), it’s only listed as a usb printer.

Running the ip a command gives:
Code: [Select]
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:01:80:68:cb:de brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.104/24 brd 192.168.1.255 scope global dynamic enp0s25
       valid_lft 75708sec preferred_lft 75708sec
    inet6 fe80::201:80ff:fe68:cbde/64 scope link
       valid_lft forever preferred_lft forever
3: wlp1s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether 0a:da:9d:c5:92:e8 brd ff:ff:ff:ff:ff:ff

Running ip a show eth0 gives:
Device “eth0” does not exist.

Runningip link ls up gives:
Code: [Select]
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
    link/ether 00:01:80:68:cb:de brd ff:ff:ff:ff:ff:ff
3: wlp1s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DORMANT group default qlen 1000
    link/ether ca:3b:a9:5b:20:bb brd ff:ff:ff:ff:ff:ff

Running ip r list gives:
Code: [Select]
default via 192.168.1.1 dev enp0s25 proto static metric 100
192.168.1.0/24 dev enp0s25 proto kernel scope link src 192.168.1.104 metric 100

Network question:
Is there nothing listed under “eth0” because I’m using TPLink devices?

Can I get the printer to work via ethernet and be available to both linux machines and any wireless devices connected to the network?

Currently, the command lsusb gives:
Code: [Select]
Bus 006 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 006: ID 03f0:5311 Hewlett-Packard OfficeJet 6300
Bus 005 Device 004: ID 046d:c408 Logitech, Inc. Marble Mouse (4-button)
Bus 005 Device 003: ID 03f0:1024 Hewlett-Packard Smart Card Keyboard
Bus 005 Device 002: ID 05e3:0604 Genesys Logic, Inc. USB 1.1 Hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Opening up CUPS, and clicking on ‘Printers’ gives:


I see that the device has an entry for its printer function and one for its fax function.

Clicking on the printer-specific entry brings up:


The printer is working OK as it is, but I would like to be able to make it available to any device on the network.

How would I go about doing this?   Would I need to disable its usb functionality and then set it up anew as a network printer?


 

Re: Trying to Understand Network
« Reply #1 on: 09 September, 2018, 11:38:27 am »
The network interface is enp0s25 instead of Eth0. It's known as predictable network interface naming. Nothing to do with the TPLink adapter - these are transparent to devices on the network.

If you want the printer to be shared then you can either share it on the PC it's USB interface is connected to but that relies on that PC being always on or install it as a network printer on each PC that needs to use it.

Re: Trying to Understand Network
« Reply #2 on: 09 September, 2018, 11:48:12 am »
Thank you, rusky.

What's 'wlpls0'?  A wireless device, not connected at the moment?

Re: Trying to Understand Network
« Reply #3 on: 09 September, 2018, 12:09:24 pm »
It's the Wi-Fi interface. What used to be WLAN0. predictable network interface naming again!
https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/