Can't connect to LAN device, but Internet OK...

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hardt68
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Location: France

Can't connect to LAN device, but Internet OK...

Post by hardt68 »

Hello,

with my current configuration, I can browse Internet, but can't connect to my devices on the local network except the gateway.
Here my configuration and researches:
* ufw disabled (initial issue discovered with ufw enabled)
* connected by wifi with fixed IP address, gateway and DNS set to 192.168.1.1
* 192.168.1.1 (Gateway) can be accessed (web inteface for admin)
* on this computer,

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[...]$ ip neigh
192.168.1.1 dev wlp3s0 lladdr 8c:f8:13:37:b8:fe STALE

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traceroute 192.168.1.16 (with gnome-nettool) displays
1	livebox.home	192.168.1.1	4.681
... nothing more happens...
* on a second computer (still LMDE2 based)

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][...]$ ip neigh
192.168.1.1 dev wlan0 ... REACHABLE
192.168.1.16 dev wlan0 ... REACHABLE

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traceroute 192.168.1.16 (with gnome-nettool) displays
1	nas.home	192.168.1.16	3.153
* Note that at test time, both computers where ON and connected to the LAN and Intternet via wifi (identical settings)

The last change I made on the system before I noticed the break in accessing the NAS (but also other devices on the LAN) is installing and USB3 <> Ethernet converter following this instructions https://www.pcsuggest.com/install-rtl8153-driver-linux/. But I have no evidences that it was the trigger !

How would you suggest to approach resolving that issue ?

Thanks in advance for any hint to get out of that situation.

Regards
Last edited by hardt68 on Sun Dec 30, 2018 4:21 am, edited 1 time in total.
=========================
hardt68 / France
LinuxMint 19.1 Cinnamon on TP Yoga 460

ajgringo619
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Posts: 1546
Joined: Thu Mar 01, 2018 8:36 pm
Location: San Diego, California, USA

Re: Can't connect to LAN device, but Internet OK...

Post by ajgringo619 »

Can you post the following (you may need to install nmap):

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ip addr show wlp3s0
nmap -sn 192.168.1.0/24
Mint 19.3 XFCE
kernel 5.3.0-42-generic
AMD FX-8350 Eight-Core w/16 GB RAM
Nvidia GeForce 960 w/2GB RAM [440.64]
Image

hardt68
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Posts: 20
Joined: Sat Apr 12, 2014 4:54 pm
Location: France

Re: Can't connect to LAN device, but Internet OK...

Post by hardt68 »

Thanks ajgringo619 for your reply. Here the result of the commands:

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[...]$ ip addr show wlp3s0
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 44:85:00:30:c6:54 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.103/0 brd 255.255.255.255 scope global wlp3s0
       valid_lft forever preferred_lft forever
    inet6 2a01:cb10:8e:7500:4685:ff:fe30:c654/64 scope global mngtmpaddr dynamic 
       valid_lft 1785sec preferred_lft 585sec
    inet6 fe80::4685:ff:fe30:c654/64 scope link 
       valid_lft forever preferred_lft forever

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[...]$ nmap -sn 192.168.1.0/24
Starting Nmap 7.40 ( https://nmap.org ) at 2018-12-30 09:16 CET
Nmap scan report for livebox.home (192.168.1.1)
Host is up (0.0048s latency).
Nmap scan report for 192.168.1.103
Host is up (0.00051s latency).
Nmap done: 256 IP addresses (2 hosts up) scanned in 3.04 seconds
eager to read you soon !
Regards
=========================
hardt68 / France
LinuxMint 19.1 Cinnamon on TP Yoga 460

hardt68
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Posts: 20
Joined: Sat Apr 12, 2014 4:54 pm
Location: France

[SOLVED] Re: Can't connect to LAN device, but Internet OK...

Post by hardt68 »

In the meantime, I found the issue:
at the time I set the fixed local IP address to 192.168.1.103, -the sub-mask has been left empty. By default the submask has been set to 0.0.0.0.
I changed it to 255.255.255.0 and everything works fine now.

I just wonder about

Code: Select all

[...]$ ip addr show wlp3s0
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
     ....
    inet 192.168.1.103/0 brd 255.255.255.255 scope global wlp3s0
Is 255.255.255.255 supposed to be the subnet setting ?

Anyway, THANKS ajgringo619 for your support and reactivity !

Regards
=========================
hardt68 / France
LinuxMint 19.1 Cinnamon on TP Yoga 460

ajgringo619
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Posts: 1546
Joined: Thu Mar 01, 2018 8:36 pm
Location: San Diego, California, USA

Re: Can't connect to LAN device, but Internet OK...

Post by ajgringo619 »

Glad you got it working.
Mint 19.3 XFCE
kernel 5.3.0-42-generic
AMD FX-8350 Eight-Core w/16 GB RAM
Nvidia GeForce 960 w/2GB RAM [440.64]
Image

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SuperBoby
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Re: [SOLVED] Re: Can't connect to LAN device, but Internet OK...

Post by SuperBoby »

hardt68 wrote:
Sun Dec 30, 2018 1:32 pm
I just wonder about

Code: Select all

[...]$ ip addr show wlp3s0
3: wlp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
     ....
    inet 192.168.1.103/0 brd 255.255.255.255 scope global wlp3s0
Is 255.255.255.255 supposed to be the subnet setting ?
No, it was the IP broadcast address for the NIC's subnet, since the mask was 0.0.0.0. Now that you set the IP/mask to 192.168.1.103/255.255.255.0, the broadcast address should be 192.168.1.255.

https://en.wikipedia.org/wiki/Broadcast_address
LMDE 3 Cindy x64 on :
Lenovo Thinkpad T410, X220 Tablet, X61

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