Im facing strange issue on virtual Ubuntu 22.04.4 server (VM). Few days ago it started to fail during basic network communication. I can ping to IP adresses but when I try ping by name it returns that it failed to resolve for few attempts and after that it ping. This repeats for every ping with name. I cannot telnet to any server by IP or name. I cannot check for updates (apt update), it says that connection failed. When I reboot the server everything work for aprox. 30 minuntes but after that it starts to fail again.
I have checked netplan settings, recreated resolve.conf (deleted and relinked), tryied to configure firewall (allow ports 43 and 53 in ufw) but without success.
I have another three servers, that were installed a configured same way without issues. VMs on same HW as faulty one.
Do you have any ideas?
I dont work with Linux servers on daily basis, so I know very little about it. If you need some info please tell me what you need and where/how to find it.
Thank you.
NMCLI output:
GENERAL.DEVICE: br-3b39fb115f90GENERAL.TYPE: bridgeGENERAL.HWADDR: 02:42:74:A0:6D:1FGENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --IP4.ADDRESS[1]: 172.18.0.1/16IP4.GATEWAY: --IP4.ROUTE[1]: dst = 172.18.0.0/16, nh = 0.0.0.0, mt =>IP6.ADDRESS[1]: fe80::42:74ff:fea0:6d1f/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: docker0GENERAL.TYPE: bridgeGENERAL.HWADDR: 02:42:71:8C:90:BEGENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --IP4.ADDRESS[1]: 172.17.0.1/16IP4.GATEWAY: --IP4.ROUTE[1]: dst = 172.17.0.0/16, nh = 0.0.0.0, mt =>IP6.GATEWAY: --GENERAL.DEVICE: eth0GENERAL.TYPE: ethernetGENERAL.HWADDR: 00:15:5D:CC:44:02GENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --WIRED-PROPERTIES.CARRIER: onIP4.ADDRESS[1]: 172.16.1.151/24IP4.GATEWAY: 172.16.1.254IP4.ROUTE[1]: dst = 0.0.0.0/0, nh = 172.16.1.254, mt >IP4.ROUTE[2]: dst = 172.16.1.0/24, nh = 0.0.0.0, mt =>IP6.ADDRESS[1]: fe80::215:5dff:fecc:4402/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: veth3136b43GENERAL.TYPE: ethernetGENERAL.HWADDR: 3E:42:68:C4:66:1CGENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --WIRED-PROPERTIES.CARRIER: onIP4.GATEWAY: --IP6.ADDRESS[1]: fe80::3c42:68ff:fec4:661c/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: veth49cb283GENERAL.TYPE: ethernetGENERAL.HWADDR: 16:3D:3A:C4:17:CEGENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --WIRED-PROPERTIES.CARRIER: onIP4.GATEWAY: --IP6.ADDRESS[1]: fe80::143d:3aff:fec4:17ce/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: vetha2f005eGENERAL.TYPE: ethernetGENERAL.HWADDR: 3A:56:CB:75:64:40GENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --WIRED-PROPERTIES.CARRIER: onIP4.GATEWAY: --IP6.ADDRESS[1]: fe80::d876:bbff:fe2b:fd1f/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: vethdec95a1GENERAL.TYPE: ethernetGENERAL.HWADDR: FE:9C:AE:DD:5F:85GENERAL.MTU: 1500GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --WIRED-PROPERTIES.CARRIER: onIP4.GATEWAY: --IP6.ADDRESS[1]: fe80::e0cc:20ff:fe7a:180d/64IP6.GATEWAY: --IP6.ROUTE[1]: dst = fe80::/64, nh = ::, mt = 256GENERAL.DEVICE: loGENERAL.TYPE: loopbackGENERAL.HWADDR: 00:00:00:00:00:00GENERAL.MTU: 65536GENERAL.STATE: 10 (unmanaged)GENERAL.CONNECTION: --GENERAL.CON-PATH: --IP4.ADDRESS[1]: 127.0.0.1/8IP4.GATEWAY: --IP6.ADDRESS[1]: ::1/128IP6.GATEWAY: --IP6.ROUTE[1]: dst = ::1/128, nh = ::, mt = 256Netplan:
network: ethernets: eth0: dhcp4: false addresses: [172.16.1.151/24] routes: - to: default via: 172.16.1.254 nameservers: addresses: [192.168.77.201,8.8.8.8] version: 2resolv.conf:
nameserver 192.168.77.201nameserver 8.8.8.8search resolvectl status:
Global Protocols: -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedresolv.conf mode: uplinkLink 2 (eth0)Current Scopes: DNS Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported DNS Servers: 192.168.77.201 8.8.8.8Link 3 (br-3b39fb115f90)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedLink 4 (docker0)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedLink 6 (vetha63a47b)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedLink 8 (veth23315da)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedLink 10 (veth1b69bb9)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupportedLink 12 (vethe4140d7)Current Scopes: none Protocols: -DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported● systemd-resolved.service - Network Name Resolution Loaded: loaded (/lib/systemd/system/systemd-resolved.service; enabled; vendor preset: enabled) Active: active (running) since Thu 2024-06-20 08:09:34 CEST; 36min ago Docs: man:systemd-resolved.service(8) man:org.freedesktop.resolve1(5) https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-managers https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients Main PID: 852 (systemd-resolve) Status: "Processing requests..." Tasks: 1 (limit: 18967) Memory: 9.1M CPU: 146ms CGroup: /system.slice/systemd-resolved.service└─852 /lib/systemd/systemd-resolvedJun 20 08:09:34 sc-hvh-app systemd[1]: Starting Network Name Resolution...Jun 20 08:09:34 sc-hvh-app systemd-resolved[852]: Positive Trust Anchors:Jun 20 08:09:34 sc-hvh-app systemd-resolved[852]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65d08458e880409bbc683457104237c7f8ec8dJun 20 08:09:34 sc-hvh-app systemd-resolved[852]: Negative trust anchors: home.arpa 10.in-addr.arpa 16.172.in-addr.arpa 17.172.in-addr.arpa 18.172.in-addr.arpa 19.172.in-addr.arpa 20.172>Jun 20 08:09:34 sc-hvh-app systemd-resolved[852]: Using system hostname 'sc-hvh-app'.Jun 20 08:09:34 sc-hvh-app systemd[1]: Started Network Name Resolution.Jun 20 08:09:57 sc-hvh-app systemd-resolved[852]: Clock change detected. Flushing caches.ls -l /etc/resolv.conf:
lrwxrwxrwx 1 root root 32 Jun 19 10:51 /etc/resolv.conf -> /run/systemd/resolve/resolv.conf