| lordievader | Good morning | 06:15 |
|---|---|---|
| YeOldHinnerk | Hi. SInce recently, I suddenly have issue with the network. My server can not even ping the DNS server (which is my router) anymore - and it could a day or so before. Don't really understand why. What to do? What can I check? The LAN settings seem all to be correct. | 11:09 |
| YeOldHinnerk | (and are unchanged from before) | 11:10 |
| YeOldHinnerk | The router doesn't seem to be the issue, it works fine for all other purposes. | 11:11 |
| YeOldHinnerk | I can still login via IPMI. | 11:11 |
| RoyK | YeOldHinnerk: ethtool <nameofnetworkdevice> will tell if the link is active | 11:16 |
| YeOldHinnerk | it even says "Link deteced" | 11:17 |
| YeOldHinnerk | I also checked with "nmcli device show eno1" | 11:18 |
| YeOldHinnerk | It all looks good. | 11:18 |
| YeOldHinnerk | but nslookup fails. | 11:18 |
| YeOldHinnerk | ";; connection timed out: no servers could be reached" | 11:19 |
| YeOldHinnerk | Did you mean something else the "link deteced" when you said "active"? | 11:20 |
| lordievader | Can you still ping the router? | 11:34 |
| YeOldHinnerk | I can from my laptop, not from my server. | 11:42 |
| lordievader | What does the server say? | 11:43 |
| YeOldHinnerk | I just clean eveything under /etc/NetworkManager and started out fresh, with everything set as it should to the best of my knowledge. Still doen't work. | 11:43 |
| YeOldHinnerk | I did restart the service of course. | 11:43 |
| lordievader | I do assume you ping the router by ip | 11:44 |
| YeOldHinnerk | ping 192.168.1.1 results in: | 11:44 |
| YeOldHinnerk | "Von 192.168.1.40 icmp_seq=xx Zielhost nicht erreichbar" | 11:45 |
| YeOldHinnerk | where xx is the count of course. | 11:45 |
| YeOldHinnerk | Yes, by ip | 11:45 |
| YeOldHinnerk | nslookup fails as well. | 11:46 |
| YeOldHinnerk | (not surprising, since ping fails). | 11:46 |
| lordievader | Do you happen to have tcpdump installed on the server? | 11:46 |
| YeOldHinnerk | yes. | 11:46 |
| YeOldHinnerk | but never used it. | 11:47 |
| YeOldHinnerk | just check. | 11:47 |
| YeOldHinnerk | btw. I have to Lan adapters in my server. | 11:47 |
| lordievader | Do you see replies to ARP requests on your interface? | 11:47 |
| YeOldHinnerk | Yes. | 11:47 |
| lordievader | Interesting, so in your arp table (`sudo arp -n`) there is a mac address in the entry for your router? | 11:49 |
| YeOldHinnerk | well, the router is in there by ip, for mac it says (unvollständig) meaning "incomplete" | 11:50 |
| === codedmart_ is now known as codedmart | ||
| lordievader | Does your firewall drop arp? | 11:51 |
| YeOldHinnerk | No it doesn't and it certainly hasn't changed. | 11:53 |
| YeOldHinnerk | don'T really know how to read the arp request - but it seems odd to me that it says something like "who has 192.168.1.1 tell 192.168.1.40". | 11:54 |
| YeOldHinnerk | Because 192.168.1.1 is the router / DNS. | 11:54 |
| YeOldHinnerk | So who is this request sent to? | 11:55 |
| YeOldHinnerk | seems a bit redundant to ask the guy by name for its name, so to say. | 11:55 |
| * ogra hands YeOldHinnerk https://de.wikipedia.org/wiki/OSI-Modell 😉 | 11:56 | |
| YeOldHinnerk | Yes, OSI, great. | 11:56 |
| ogra | (ARP operates on a lower layer .. names are not known there) | 11:57 |
| YeOldHinnerk | Ah. | 11:57 |
| lordievader | ARP is used to translate ip addresses (layer 3) to mac addresses (layer 2). ARP requests are broadcast to the lan. Your router should respond with, 'hi, here I am'. That way your server learns the mac-address of the router. | 11:57 |
| lordievader | YeOldHinnerk: But do you only see the outgoing ARP requests? | 11:57 |
| YeOldHinnerk | Yes, I see outgoing ARP requests. | 11:58 |
| ogra | have you wiggled the cable yet ? 😄 | 11:58 |
| YeOldHinnerk | Yes :) | 11:59 |
| YeOldHinnerk | I really did. | 11:59 |
| YeOldHinnerk | What is interesting, in the arp I occasionaly see a "RT-AC88U" racing through, which is my router model. | 11:59 |
| YeOldHinnerk | If it was just sending into nowehere - how would it know that? | 12:00 |
| lordievader | <lordievader "YeOldHinnerk: But do you only se"> The hidden question here was, do you see replies? | 12:02 |
| YeOldHinnerk | I do not see any ARP replies. I guess I don't really understand what I'm seeing there. Just a sec. | 12:06 |
| YeOldHinnerk | Ok, so, what I see are ARP requests and also some lines which start either with STP or LLDP | 12:13 |
| lordievader | But no ARP replies? | 12:13 |
| YeOldHinnerk | LLDP contains the routers name. | 12:13 |
| YeOldHinnerk | no. | 12:13 |
| YeOldHinnerk | no arp replies. | 12:14 |
| lordievader | There is your problem. | 12:14 |
| YeOldHinnerk | ok. how to fix it? | 12:14 |
| lordievader | Erm, well the problem lies outside of the server (tcpdump listens before the firewall). So you need to figure out why the router does not reply to your arp requests. Are they not reaching the router, do the replies get dropped somewhere in the return path, etc. | 12:18 |
| YeOldHinnerk | If I look at nmcli device show eno2 it gives the correct DNS, state is connected ,.... | 12:18 |
| YeOldHinnerk | I really doubt it is the router, since that das worked before | 12:18 |
| YeOldHinnerk | has | 12:18 |
| YeOldHinnerk | I guess, I'll sign into the router and check the oppsite direction... | 12:19 |
| lordievader | You are clearly new to networking 😛 | 12:19 |
| === JanC is now known as Guest65907 | ||
| === JanC_ is now known as JanC | ||
| YeOldHinnerk | Never had any issues like that. | 12:23 |
| YeOldHinnerk | SO there was no need. | 12:23 |
| coreycb | jamespage: ceph is building now and on it's way to wallaby-updates | 12:57 |
| coreycb | successfully, that is | 12:57 |
| jamespage | great thanks coreycb | 12:57 |
| YeOldHinnerk | I have to admit that it is a bit confusing to read up to it. In particular since tools/services have changed. My understanding is, that netplan is the "network manager", not "NetworkManager", which is a bit confusing in itself. Anyway, for netplan, the config folder was empty for me, no *.yaml files. Also when I look up how to setup netplan, I find | 13:27 |
| YeOldHinnerk | quite different entries for renderer for example. I guess there's more than one way leading to rome, but still... | 13:27 |
| YeOldHinnerk | Ok, back with my networking issues on my unbuntu server (20.04). | 15:07 |
| YeOldHinnerk | I have messed quite a bit with it trying to fix it. I think it is time for a clean start. Can someone point me to a good guideline how to set it up? I found plenty, but they all differ in some details, so I don't really know which to use. | 15:09 |
| YeOldHinnerk | My server has two network adapters. I currently have access to my server via IPMI. Earler, we found that somehow no ARP replies are reaching the server - or the requests not even the router. Anyway, the server was seeing the router earlier this week. The only "change" since then (and before my rescue tries) was a power down... | 15:11 |
| YeOldHinnerk | As someone mentioned earlier, I'm certainly not an expert on networking. | 15:11 |
| lordievader | To respond to an earlier comment, netplan is a sort of frontend for other network configuration utilities, like systemd-networkd. | 15:14 |
| lordievader | Personally I don't like netplan. I typically use systemd-networkd or ifupdown on my servers. | 15:15 |
| YeOldHinnerk | ah, missed that comment | 15:15 |
| YeOldHinnerk | ok, removed *.yaml from /etc/netplan and did apply. Started systemd-networkd | 15:21 |
| leftyfb | YeOldHinnerk: I can tell you, on a fresh install, netplan is not your issue. Removing it should only be based on some personal opinion | 16:02 |
| YeOldHinnerk | Well, it is not a fresh install. But I believe you, that netplan is not in itself the issue. | 16:03 |
| YeOldHinnerk | But I need to follow one single plan. I'm not sure which one that shloud be, netplan or whatever. | 16:03 |
| YeOldHinnerk | My gut feeling tells me, that I may have been messing up more when trying to fix the original issue, whih I still believe must have some simple cause. | 16:04 |
| leftyfb | YeOldHinnerk: you should put your netplan config back so you can troubleshoot with a standard configuration | 16:04 |
| YeOldHinnerk | but there was no yaml file when I began. I only added it when trying to fix my issue. | 16:05 |
| leftyfb | YeOldHinnerk: for now, can you just set 1 of the interfaces to dhcp? | 16:05 |
| leftyfb | YeOldHinnerk: https://netplan.io/examples/#using-dhcp-and-static-addressing | 16:05 |
| YeOldHinnerk | using netplan or what tool? | 16:05 |
| leftyfb | YeOldHinnerk: using netplan | 16:06 |
| YeOldHinnerk | will do, give me a moment. | 16:06 |
| YeOldHinnerk | do i need to switch off any other services first? | 16:07 |
| leftyfb | YeOldHinnerk: what other services are running? What's this machine used for? | 16:08 |
| YeOldHinnerk | It is my private machine, currently only me is using it. | 16:08 |
| YeOldHinnerk | I was just lloking into systemd-networkd | 16:09 |
| YeOldHinnerk | what about NetworkManager? | 16:09 |
| leftyfb | YeOldHinnerk: if it's not doing anything, then I would just wipe it and start over. It's going to be a LOT quicker than trying to diagnose whatever is wrong with it | 16:09 |
| YeOldHinnerk | ah, no. I have already setup nextcloud, minidlna and so on | 16:10 |
| YeOldHinnerk | all was working until a short time ago... | 16:10 |
| leftyfb | YeOldHinnerk: I did ask you what services were running on it and what it was used for. You did not specify any services | 16:10 |
| YeOldHinnerk | Sorry, I thought you meant in this specific contect of networking. | 16:11 |
| leftyfb | YeOldHinnerk: btw, ignore NetworkManager with Ubuntu server. It's not used | 16:11 |
| leftyfb | YeOldHinnerk: what does your network look like? Any VLAN's? multiple subnets on the same physical network? | 16:12 |
| YeOldHinnerk | nope, really simple setup. | 16:13 |
| YeOldHinnerk | the server is connected via lan with the router. | 16:13 |
| YeOldHinnerk | no vlan, no multile subnets. | 16:14 |
| YeOldHinnerk | I just created the yaml file for dhcp. | 16:14 |
| leftyfb | YeOldHinnerk: and the router is setup as a dhcp server? You have a laptop set to dhcp as well? The server should, in theory just get an ip address via dhcp from the router correct? | 16:14 |
| YeOldHinnerk | I also stopped NetworkManager. | 16:14 |
| YeOldHinnerk | Only the router serves as dhcp | 16:14 |
| YeOldHinnerk | The laptop I'm currently writing from is using that router as well, via wlan. | 16:14 |
| smoser | rbasak: how much do you care about things like this: | 16:14 |
| smoser | https://paste.ubuntu.com/p/2ChM7NW7MJ/ | 16:14 |
| leftyfb | YeOldHinnerk: I don't understand why you have NetworkManager installed. Why/how was that installed and running? | 16:15 |
| smoser | ^ that is to say, 'git-ubuntu import dracut' fails. | 16:15 |
| YeOldHinnerk | I think that was the default. I don't think I changed that. | 16:15 |
| leftyfb | YeOldHinnerk: NetworkManager (network-manager) is not installed in ubuntu server by default | 16:16 |
| leftyfb | YeOldHinnerk: it's very possible this could be causing your issue, having multiple network tools managing the network | 16:17 |
| YeOldHinnerk | but NetworkManager is disabled now. | 16:18 |
| leftyfb | YeOldHinnerk: try running sudo apt-get remove --dry-run --autoremove network-manager # and take notice of what it wants to remove. See if any of your services you are running on it are in that list | 16:18 |
| YeOldHinnerk | I just applied the netplan dhcp settings | 16:18 |
| YeOldHinnerk | beware, currently the server has no internet connection. Anything that I remove can not easily be restored. Should I continue anyway? | 16:19 |
| leftyfb | YeOldHinnerk: it should only be a dry-run and not actually do anything | 16:19 |
| YeOldHinnerk | right | 16:19 |
| YeOldHinnerk | autoremove can not be combined with dryrun :) | 16:21 |
| YeOldHinnerk | (or rather with other options) | 16:21 |
| leftyfb | ok, then leave it out | 16:21 |
| YeOldHinnerk | I need to take a break, unfortuneately. | 16:21 |
| leftyfb | leave out autoremove | 16:21 |
| YeOldHinnerk | Got some work to do. I'll be back in a little bit. | 16:21 |
| YeOldHinnerk | Thank you for helping! | 16:22 |
| rbasak | smoser: I care that no import fails :) | 18:50 |
| rbasak | Thank you for the report! | 18:50 |
| smoser | rbasak: ok, if i see failures like taht, what should i do? | 19:20 |
| smoser | and how far are we from the archive being git-ubuntu'd | 19:20 |
| smoser | ? | 19:20 |
| rbasak | smoser: bug report to https://bugs.launchpad.net/usd-importer please. I made a note to file a bug for this one - your pastebin is enough. | 19:24 |
| rbasak | smoser: just need to fix up the patches-applied imports. That's the one major task remaining. Still a few months away in practice I think. In the meantime I have some branches landing for adopting rich history from any uploader, and making it easier/quicker for us to add packages to import. If you have any packages in particular you'd like maintained in git-ubuntu right now, we can add them. | 19:26 |
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