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Distribution: Ubuntu 16.04 lts desk; Ubuntu 14.04 server
Posts: 366
Rep:
network garfuzled
Friends--
The short version of my saga:
Synopsis: previously used this computer to connect to network and internet via vpn, and had no problems. Yesterday I started having problems (running now in the office, so a direct connection to the lan), and they get worse as they get better. Read on, if you dare.
Change yesterday: I had a reliable tech service move a graphics board (GeForce GTX 1060 3GB) from another computer into this one. There are three screens attached, each an hp lv2311.
sudo ip link set enp3s0 down
sudo ip addr flush enp3s0
sudo ip link set enp3s0 up
sudo dhclient -r
sudo dhclient enp3s0
After this I can connect to the Internet and to the lan. All works fine, for a bit....
But wait, there's more:
1. It does not hold after a reboot.
2. After a few minutes running a browser (firefox or chrome), kworker starts using 60-80% of cpu, and the browser is usually over 45%. Consequently, the computer is unusable. If I renice under top to +19, it helps momentarily, but not enough to even move the cursor around.
Other things going on that might have clues or just be irrelevant:
A. At bootup it does not mount directories from two servers which are in fstab. This is a minor annoyance. It says something about cifs error connecting to socket, right at the end of bootup. Perhaps it is because the network is not connecting properly.
B. One message that scrolled past at some time said
Code:
nouveau DRM: GPU lockup--switching to software fbcon.
C. Early on, trying to get it to ping even the lan, I tried to set up netplan. There were no files in /etc/netplan, and I added 01-network-manager-all.yaml, and also tried sudo netplan generate and sudo netplan apply and they did nothing as far as I could see. Even after re-installing netplan which it said was the latest version. Some other commands I issued at various times which sometimes helped me connect to the lan, and sometimes made no difference, and none persisted after a reboot:
Code:
sudo ifconfig enp3s0 192.168.0.13
sudo nmcli networking off
sudo nmcli networking on
D. I have in this process, when I was connected, run
Synopsis: previously used this computer to connect to network and internet via vpn, and had no problems. Yesterday I started having problems (running now in the office, so a direct connection to the lan), and they get worse as they get better. Read on, if you dare.
Change yesterday: I had a reliable tech service move a graphics board (GeForce GTX 1060 3GB) from another computer into this one. There are three screens attached, each an hp lv2311.
The computer: 4 cores @ 3.20GHz; 7.6G memory. Running 20.04.4 LTS.
Symptoms: At bootup, I currently can ping other computers on the lan, but not google.com. I get “Temporary failure in name resolution”
sudo ip link set enp3s0 down
sudo ip addr flush enp3s0
sudo ip link set enp3s0 up
sudo dhclient -r
sudo dhclient enp3s0
After this I can connect to the Internet and to the lan. All works fine, for a bit....But wait, there's more:
1. It does not hold after a reboot.
2. After a few minutes running a browser (firefox or chrome), kworker starts using 60-80% of cpu, and the browser is usually over 45%. Consequently, the computer is unusable. If I renice under top to +19, it helps momentarily, but not enough to even move the cursor around.
Other things going on that might have clues or just be irrelevant:
A. At bootup it does not mount directories from two servers which are in fstab. This is a minor annoyance. It says something about cifs error connecting to socket, right at the end of bootup. Perhaps it is because the network is not connecting properly.
B. One message that scrolled past at some time said
Code:
nouveau DRM: GPU lockup--switching to software fbcon.
C. Early on, trying to get it to ping even the lan, I tried to set up netplan. There were no files in /etc/netplan, and I added 01-network-manager-all.yaml, and also tried sudo netplan generate and sudo netplan apply and they did nothing as far as I could see. Even after re-installing netplan which it said was the latest version. Some other commands I issued at various times which sometimes helped me connect to the lan, and sometimes made no difference, and none persisted after a reboot:
Code:
sudo ifconfig enp3s0 192.168.0.13
sudo nmcli networking off
sudo nmcli networking on
D. I have in this process, when I was connected, run
So the system is up to date. This whole thing has me stumped. Can you help me un-garfuzle this network?
Bolded and underlined two things above for emphasis. This 'reliable tech service' moved a board, and now things aren't working...and you're clearly getting an error that tells you that the GPU (the graphics board) is locking up, so it's shifting to software rendering to drive three screens. Don't be surprised that your system is slow.
The network errors regarding the CIFS mounts are there because you are (obviously) having a network issue...so trying to mount a network drive with no network would give you an error. Since you can ping systems on the LAN but not Internet, that says that you either don't have a default route set, or your DNS isn't configured. You don't say how you're pinging things (name or address?), but since it says "failure in name resolution", that's a clue. Flailing at netplan, and randomly changing things network wise isn't a good idea...mainly because you didn't have to do this things BEFORE, did you??
...the 'reliable tech service' apparently didn't do much research, since the specific nouveau drivers have issues with that card, apparently. The nVidia drivers do work, and can be installed easily. As far as your network configs go, I would remove ANYTHING that you've done and get back to where you were, and diagnose things from there. Easiest thing to do would be to select your interface, and tell it to use DHCP, and get a 'fresh' config/DNS/etc., and verify it's working. At that point, diagnostics should be easier, since you won't have changed a bunch of things without knowing why/what they do, making it much harder to fix.
Distribution: Ubuntu 16.04 lts desk; Ubuntu 14.04 server
Posts: 366
Original Poster
Rep:
TB0ne--
Thank you, thank you!
I have read your reply two times, and it is starting to sink in. What I think I have to do is:
1. install the proper nvidia driver; and
2. do something with dhcp; and
3. most importantly: get the network up and running.
This second thing is the puzzle for me. Although I have been running this network for 18 years, I have always used static addresses, and I get confused about having dhcp assign addresses. For instance, I have the router set to hand out 192.168.0.13 to this computer based on its mac address. So could you take me a bit more slowly through the process of dhcp?
The third thing, putting it back, is unlikely because unlike my usual pattern, I did not make good notes of what I did. (No, I did not have to do netplan and all those things before the card change. I admit it. ) I could use the history command and get some hints, but that is all. Is there a way to just start from scratch? Is that what your advice to use dhcp does?
I am the one to blame for not researching. I only asked the tech service to physically move the card. He did say there is a way to get the two on board video ports to work with the new card by tweaking bios. I thought about moving two of the monitors to those ports to see if that works. But messing with bios is tricky.
Thank you very much for parsing through my long story and giving me light!
I have read your reply two times, and it is starting to sink in. What I think I have to do is:
1. install the proper nvidia driver; and
2. do something with dhcp; and
3. most importantly: get the network up and running.
This second thing is the puzzle for me. Although I have been running this network for 18 years, I have always used static addresses, and I get confused about having dhcp assign addresses. For instance, I have the router set to hand out 192.168.0.13 to this computer based on its mac address. So could you take me a bit more slowly through the process of dhcp?
The third thing, putting it back, is unlikely because unlike my usual pattern, I did not make good notes of what I did. (No, I did not have to do netplan and all those things before the card change. I admit it. ) I could use the history command and get some hints, but that is all. Is there a way to just start from scratch? Is that what your advice to use dhcp does?
If you have 18 years experience with networks, I can't imagine why DHCP would be a puzzle, or that you'd not know what it is/does. You've asked about SSH, VPN circuits, and network protocols going back at least seven years here. If you have a DHCP server on your network, it'll give out the proper DNS servers/address/netmask, in order to be able to function. If you can't undo the things you did, then they may very well step on whatever else is going on, and not make any difference at all. If you configured your router to give things out based on MAC addresses, I can't fathom why you don't know what the address/netmask is, or what the DNS servers are to do basic research on your connectivity issues. You have everything you need, and seemingly have the knowledge of what they are. You know what your resolv.conf file should contain...so why is any of this confusing??
Either use DHCP or not...since you configured your router, did you set it up to be a DHCP server, and give out addresses/information correctly???
Quote:
I am the one to blame for not researching. I only asked the tech service to physically move the card. He did say there is a way to get the two on board video ports to work with the new card by tweaking bios. I thought about moving two of the monitors to those ports to see if that works. But messing with bios is tricky.
Not sure why you'd pay anyone to simply move a card, when it's just a matter of plugging it in. And now you mention "two on board video ports"??? How are the monitors connected (VGA? DVI? DisplayPort? HDMI?) and to what??? What kind of computer?? And if this 'reliable tech service' is telling you about 'tweaking bios', it's odd that they couldn't actually DO IT while they were there, isn't it?? And even more suspicious that your network had problems after they were done....almost like they want you to call back for more 'reliable' service to fix your network and video issues.
Again: there is nothing much to 'sink in'. Load the correct nVidia drivers using the steps/links that were looked up for you and given to you. If you can't remember how to undo whatever it is you did to your network, then you probably should reload your OS from scratch and start there, because we can't guess as to what you changed (if you can't remember it), so we sure can't tell you what to do to change it back. You also haven't given us details about your system, because the CPU specs/memory don't have a lot to do with the ports on the system, or how you have things hooked up.
You mentioned that your router assigns a specific IP based on the interface MAC.
That tells me you were already using DHCP and you should have been aware of that.
It also should in no way have affected the display or memory usage, unless the network interface was also modified by the "reliable tech service" you used.
Nothing related to the network should have been directly affected by the installation of a GPU, though the heavy CPU load as a result of not having hardware acceleration for the GPU would certainly interfere with everything else being done on the PC.
Your biggest issue is that you saw one thing failing and started randomly attempting to make a fix for that without considering what had changed and why the failure was occuring.
Rule #1 is always suspect what changed rather than what has been reliably working for a long time.
Instead you thrashed your network instead of solving the problem.
Rule #2 is to always do your research before you make a change to be aware of the potential problems you may encounter.
In this case it is well known that the nouveau driver is not capable of using hardware acceleration with nvidia GPUs so you should have known that the nvidia driver was mandatory for your needs.
Remember the 7 Ps of obtaining good results when preparing for any action. (Proper Prior Planning Prevents Piss-Poor Performance)
The "reliable tech service" wasn't reliable nor knowledgeable. They should have been aware to remind you about the need for the nvidia drivers. I suspect they were minimally trained hardware grunts only capable of installing the card and knew little about the need for drivers for it. My 10 year old grandson can install a card, but does not have the knowledge about drivers.
Last edited by computersavvy; 07-22-2022 at 08:36 PM.
@computersavvy
Agree I made several mistakes. What's the next step, please?
You were told what the next steps were before...did you not read them??
You undo whatever it is you did on your computer to 'fix' your network. You have provided no details about how you're doing anything or what you did, but on Gnome and KDE, there are network management applets on the task bar...trivial to delete/add a network connection. Since you've been doing networking for 18 years, you should be well aware that you've configured your router to dole out IP addresses based on MAC addresses, and that your computer is already set up to do this. Delete your existing connection....add a new one, using DHCP. Again, you know what this is and does since by your own admission you configured your router to do it.
Beyond that, reload your OS from scratch; follow the links that had to be looked up for you about doing the install of 20.04 with the nVidia drivers.
DNS was mentioned to you early on here, and that was apparently the cause of you being 'garfuzled' (whatever that means). If you don't want to perform diagnostics for us here, it's odd that you can seem to do them for other forums. Good luck.
I think the tech moved your ethernet card, which made the naming change either by Network Manager or a config file. The slot number is part of the naming convention. So that is why you simulate
what it does (bring interface up, and run dhcp on it) works, instead of just saying it "interface up and auto ipv4" in a config file and why it isn't preserved on boot.
That is also why DNS does not work, I assume you were getting DNS servers from DHCP.
ls /sys/class/net to see the network interface mappings.
I think the tech moved your ethernet card, which made the naming change either by Network Manager or a config file. The slot number is part of the naming convention. So that is why you simulate what it does (bring interface up, and run dhcp on it) works, instead of just saying it "interface up and auto ipv4" in a config file and why it isn't preserved on boot. That is also why DNS does not work, I assume you were getting DNS servers from DHCP.
ls /sys/class/net to see the network interface mappings.
The OP said the only thing the tech did was install a video card...and how would moving a card from one slot to another, rename the network interface??? And the OP stated the interface didn't change...they were able to see machines on the same network, just not others. They had no DNS, and flailed at it, changing a bunch of things (and didn't know how to change them back), despite having 18 years experience.
They had their router set to do DHCP based on MAC address; apparently, they changed it back and things worked.
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network garfuzled
) I could use the history command and get some hints, but that is all. Is there a way to just start from scratch? Is that what your advice to use dhcp does?
