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crabbyfogey 04-01-2017 04:47 PM

Weird internet connection
 
Last week started having an issue with my quasi-new laptop. Thinks it's connected to internet, but won't access it. Did the usual modem stuff: reset/turned off-nothing. Changed ethernet cables-still nothing. Dusted off my old laptop (also runs MNT17), hooked it up and it connected w/o any trouble. One curious thing is that once the old laptop connects, the newish one has no trouble using the connection. Compared network settings and the setting on the primary laptop has 2 DNS numbers (old one doesn't) at networking/wired. ??? Looks like this: ###.###.#.# ###.###.#.## I know nothing about networks, could that be the problem? Tried reading man resolveconf, didn't understand much of it.

sham1 04-01-2017 05:23 PM

Have you tried to invoke either dhcpcd or dhclient with your network interface name as their arguments, like this:

Code:

dhcpcd enp1s0
(obviously change dhcpcd to dhclient if dhcpcd isn't installed and enp1s0 to your actual interface name, that you can check with the command "ip addr")

The problem you are describing sounds distinctly like the kind of problem where your computer isn't sending a DHCP request automatically, thusly leading to you not having an IP address, which means that you cannot connect to the Internet because your packets have no address to set as the "source"-address of the package. Which is needed in other to get packages back to your computer from servers.

jsbjsb001 04-01-2017 05:43 PM

Quote:

Originally Posted by crabbyfogey (Post 5691412)
Last week started having an issue with my quasi-new laptop. Thinks it's connected to internet, but won't access it. Did the usual modem stuff: reset/turned off-nothing. Changed ethernet cables-still nothing. Dusted off my old laptop (also runs MNT17), hooked it up and it connected w/o any trouble. One curious thing is that once the old laptop connects, the newish one has no trouble using the connection. Compared network settings and the setting on the primary laptop has 2 DNS numbers (old one doesn't) at networking/wired. ??? Looks like this: ###.###.#.# ###.###.#.## I know nothing about networks, could that be the problem? Tried reading man resolveconf, didn't understand much of it.

A few questions:

1) Has your new laptop ever been able to access the Internet?
2) What makes you say "Thinks it's connected to internet"?
3) Is it safe to assume you mean your "primary" laptop is referring to your new laptop?
4) Am I right in thinking that when you connect your old laptop, the newer one DOES access the Internet?

My first thought is given you said (if I have read what you have said correctly), when you connect your old laptop the newer one DOES access the Internet, that would seem to me to be a clue. The 2 DNS IP addresses are normal.

Can you post the output of the following commands;

Code:

ifconfig -a
route


crabbyfogey 04-01-2017 05:43 PM

Looking at the network settings,there is an IP add listed exactly where it's supposed to be. More than one in fact, why would it suddenly stop sending it automatically?

Don't know what this means:

Have you tried to invoke either dhcpcd or dhclient with your network interface name as their arguments, like this:

Code:

dhcpcd enp1s0

(obviously change dhcpcd to dhclient if dhcpcd isn't installed and enp1s0 to your actual interface name, that you can check with the command "ip addr")

jsbjsb001 04-01-2017 05:51 PM

Quote:

Originally Posted by crabbyfogey (Post 5691423)
Looking at the network settings,there is an IP add listed exactly where it's supposed to be. More than one in fact, why would it suddenly stop sending it automatically?

Code:

dhcpcd enp1s0

(obviously change dhcpcd to dhclient if dhcpcd isn't installed and enp1s0 to your actual interface name, that you can check with the command "ip addr")

dhcp means "dynamic host configuration protocol", which is basically your routers way of giving out IP addresses to devices connected to it. dhcpd is the service that actually does it.

What do you mean by "IP add" and can you please answer the previous questions asked. Thanks.

crabbyfogey 04-01-2017 05:55 PM

New laptop has never had an internet connection problem, until last week.

I have a window that pops up to tell me when it's connected, also when I click on icon, shows it's connected.

Sorry, primary laptop is the new one (Lenovo)

After the old one establishes the connection, Lenovo has no problem using it. I can even turn off the old one and Lenovo still uses connection.

----------------------------------
morgan@morgan-Lenovo-G50-80 ~ $ ifconfig -a
eth0 Link encap:Ethernet HWaddr 50:7b:9d:00:c6:2d
inet addr:192.168.0.5 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::527b:9dff:fe00:c62d/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:46388 errors:0 dropped:0 overruns:0 frame:0
TX packets:35515 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:58735343 (58.7 MB) TX bytes:3203023 (3.2 MB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:961 errors:0 dropped:0 overruns:0 frame:0
TX packets:961 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:87322 (87.3 KB) TX bytes:87322 (87.3 KB)

wlan0 Link encap:Ethernet HWaddr e4:f8:9c:02:23:80
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

--------------------------
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.0.1 0.0.0.0 UG 0 0 0 eth0
192.168.0.0 * 255.255.255.0 U 1 0 0 eth0

jsbjsb001 04-01-2017 06:00 PM

Quote:

Originally Posted by crabbyfogey (Post 5691429)
New laptop has never had an internet connection problem, until last week.

What's changed since last week?

As, if it was working before (as what you are saying seems to suggest, correct me if I'm wrong), then it sounds like something has changed and is likely related to the problem you are currently having.

crabbyfogey 04-01-2017 06:17 PM

Entirely agree with that. What's got me so confused is that if something is working, I don't mess with it. I have no idea where the second IP address came from, it wasn't there initially. That's why I suspected that had something to do with my problem. The only other thing I did was a couple of updates from the update manager notification.

jsbjsb001 04-01-2017 06:22 PM

Quote:

Originally Posted by crabbyfogey (Post 5691437)
Entirely agree with that. What's got me so confused is that if something is working, I don't mess with it. I have no idea where the second IP address came from, it wasn't there initially. That's why I suspected that had something to do with my problem. The only other thing I did was a couple of updates from the update manager notification.

I have just noticed from your route command output, you have a gateway of 255.255.255.0, instead of 255.255.255.255 which is what I think it should be, but still a little confused given you said that it was working last week.

What exactly do you mean by "The only other thing I did was a couple of updates from the update manager notification.", what is the update manager notification?

ferrari 04-01-2017 06:27 PM

So your IP address and kernel routing table suggest you are configured correctly for your LAN. Can you ping the gateway successfully
Code:

ping 192.168.0.1
Ping a well known internet address eg google DNS server?
Code:

ping 8.8.8.8
Ping by name?
Code:

ping google.com
If it is only the latter that fails, it is a likely name server issue
Code:

grep "name" /etc/resolv.conf

ferrari 04-01-2017 06:30 PM

Quote:

I have just noticed from your route command output, you have a gateway of 255.255.255.0, instead of 255.255.255.255 which is what I think it should be, but still a little confused given you said that it was working last week.
No, that is ok. Mine for reference
Code:

Kernel IP routing table
Destination    Gateway        Genmask        Flags Metric Ref    Use Iface
0.0.0.0        192.168.1.1    0.0.0.0        UG    100    0        0 eth0
192.168.1.0    0.0.0.0        255.255.255.0  U    100    0        0 eth0


jsbjsb001 04-01-2017 06:33 PM

Quote:

Originally Posted by ferrari (Post 5691444)
No, that is ok. Mine for reference
Code:

Kernel IP routing table
Destination    Gateway        Genmask        Flags Metric Ref    Use Iface
0.0.0.0        192.168.1.1    0.0.0.0        UG    100    0        0 eth0
192.168.1.0    0.0.0.0        255.255.255.0  U    100    0        0 eth0


Thanks for that, I said that because mine is 255.255.255.255
But thanks again.

crabbyfogey 04-01-2017 07:11 PM

Ping result--does this over and over:
Lenovo-G50-80 ~ $ ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
64 bytes from 192.168.0.1: icmp_seq=1 ttl=64 time=0.472 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=64 time=0.459 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=64 time=0.426 ms
64 bytes from 192.168.0.1: icmp_seq=4 ttl=64 time=0.474 ms
64 bytes from 192.168.0.1: icmp_seq=5 ttl=64 time=0.488 ms
-------------------------
Lenovo-G50-80 ~ $ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=59 time=10.7 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=59 time=10.5 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=59 time=10.8 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=59 time=10.4 ms
64 bytes from 8.8.8.8: icmp_seq=5 ttl=59 time=10.7 ms
------------------------
Lenovo-G50-80 ~ $ ping google.com
PING google.com (172.217.12.14) 56(84) bytes of data.
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=1 ttl=57 time=10.1 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=2 ttl=57 time=10.5 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=3 ttl=57 time=9.77 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=4 ttl=57 time=9.78 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=5 ttl=57 time=10.4 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=6 ttl=57 time=10.2 ms
64 bytes from den02s02-in-f14.1e100.net (172.217.12.14): icmp_seq=7 ttl=57

Is that successful?

jsbjsb001 04-01-2017 07:17 PM

Quote:

Originally Posted by crabbyfogey (Post 5691457)
Is that successful?

Yes, now what's the answer to my other question in post #9 ?

crabbyfogey 04-01-2017 07:24 PM

Update manager is software that notifies you when updates are available. Icon in panel tells you your system is up-to-date or needs something done. That's how I'm notified that Firefox, Tbird, etc has a new version, for example. The updates are ranked according to importance/risk.


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