Undiagnosable lack of ability to connect to some of the InterNet

Foreword:

I am unable to access certain websites via certain methods. Some websites are not permanently unavailable, but some are. I shall use “reddit.com” as the example, because it is permanently unavailable, except one time when it decided to be. ¯\_(ツ)_/¯ However, this additionally includes “http://192.168.0.1”, which is the address of my router. I am most confused by how I am unable to access that whilst remaining able to access some of the internet, especially because this computer is solely connected via ethernet.

I am unable to provide any pictures to demonstrate this problem, because I am unable to upload them to “ask.fedoraproject.org”. I expect that it necessitates connection to a different subdomain, thus causing this problem to present itself again.

Problem:

I am unable to access “reddit.com” via firefox and chromium-browser. No error-message is presented by firefox, but chromium-browser provides “ERR_NAME_NOT_RESOLVED”.

This occurred for approximately 6 months 1 or 2 years previous to now. I was similarly unable to diagnose it, but the problem merely disappeared eventually. I do not possess that luxury currently.

Diagnosis:

I have reinitialized my router via every method available. It is connected to Sky Broadband, because I am situated within England. This has not affected anything. However, please know that this connection to the internet has never been significantly stable for any user.

I have configured the Domain Name System servers that this computer connects to via “systemsettings5” to be, for Internet Protocol version 4, “1.1.1.1,1.0.0.1”; and, for Internet Protocol version 6, “2606:4700:4700::64,2606:4700:4700::6400”. This did not appear to remediate the problem, although…

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ resolvectl status
Global
       Protocols: LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported
resolv.conf mode: stub

Link 2 (enp5s0)
    Current Scopes: DNS LLMNR/IPv6
         Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: 2606:4700:4700::64
       DNS Servers: 2606:4700:4700::64 2606:4700:4700::6400
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemd-resolve --status
Global
       Protocols: LLMNR=resolve -mDNS -DNSOverTLS DNSSEC=no/unsupported
resolv.conf mode: stub

Link 2 (enp5s0)
    Current Scopes: DNS LLMNR/IPv6
         Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: 2606:4700:4700::64
       DNS Servers: 2606:4700:4700::64 2606:4700:4700::6400
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemd-resolve status

…demonstrates that the configuration appears to have applied.

However, interestingly, I am able to resolve any domain that I desire, although solely whilst “file:///usr/lib/systemd/system/systemd-resolved.service” is operative:

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemctl status systemd-resolved
● systemd-resolved.service - Network Name Resolution
     Loaded: loaded (/usr/lib/systemd/system/systemd-resolved.service; disabled; vendor preset: enabled)
     Active: active (running) since Mon 2022-08-08 13:01:50 BST; 33min 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: 200152 (systemd-resolve)
     Status: "Processing requests..."
      Tasks: 1 (limit: 38333)
     Memory: 4.0M
        CPU: 129ms
     CGroup: /system.slice/systemd-resolved.service
             └─ 200152 /usr/lib/systemd/systemd-resolved

Aug 08 13:01:49 1656943212 systemd[1]: Starting systemd-resolved.service - Network Name Resolution...
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: Positive Trust Anchors:
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65d08458e880409bbc683457104237c7f8ec8d
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: Negative trust anchors: home.arpa 10.in-addr.arpa 16.172.in-addr.arpa 17.172.in-addr.arpa 18.172.in-ad>
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: Using system hostname '1656943212'.
Aug 08 13:01:50 1656943212 systemd[1]: Started systemd-resolved.service - Network Name Resolution.
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: enp5s0: Bus client set DNS server list to: 2606:4700:4700::64, 2606:4700:4700::6400
Aug 08 13:01:52 1656943212 systemd-resolved[200152]: Using degraded feature set UDP instead of UDP+EDNS0 for DNS server 2606:4700:4700::64.
Aug 08 13:03:01 1656943212 systemd-resolved[200152]: Flushed all caches.
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ nslookup reddit.com
Server:         127.0.0.53
Address:        127.0.0.53#53

Non-authoritative answer:
Name:   reddit.com
Address: 151.101.1.140
Name:   reddit.com
Address: 151.101.193.140
Name:   reddit.com
Address: 151.101.129.140
Name:   reddit.com
Address: 151.101.65.140
Name:   reddit.com
Address: 2a04:4e42::396
Name:   reddit.com
Address: 2a04:4e42:400::396
Name:   reddit.com
Address: 2a04:4e42:200::396
Name:   reddit.com
Address: 2a04:4e42:600::396
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig reddit.com

; <<>> DiG 9.16.31-RH <<>> reddit.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 38863
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;reddit.com.                    IN      A

;; ANSWER SECTION:
reddit.com.             63      IN      A       151.101.65.140
reddit.com.             63      IN      A       151.101.1.140
reddit.com.             63      IN      A       151.101.129.140
reddit.com.             63      IN      A       151.101.193.140

;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Aug 08 13:35:28 BST 2022
;; MSG SIZE  rcvd: 103
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig @127.0.0.53 reddit.com

; <<>> DiG 9.16.31-RH <<>> @127.0.0.53 reddit.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62683
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;reddit.com.                    IN      A

;; ANSWER SECTION:
reddit.com.             51      IN      A       151.101.193.140
reddit.com.             51      IN      A       151.101.1.140
reddit.com.             51      IN      A       151.101.129.140
reddit.com.             51      IN      A       151.101.65.140

;; Query time: 0 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Aug 08 13:35:40 BST 2022
;; MSG SIZE  rcvd: 103
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ resolvectl query reddit.com
reddit.com: 2a04:4e42:400::396                 -- link: enp5s0
            2a04:4e42:600::396                 -- link: enp5s0
            2a04:4e42:200::396                 -- link: enp5s0
            2a04:4e42::396                     -- link: enp5s0
            151.101.193.140                    -- link: enp5s0
            151.101.1.140                      -- link: enp5s0
            151.101.65.140                     -- link: enp5s0
            151.101.129.140                    -- link: enp5s0

-- Information acquired via protocol DNS in 364us.
-- Data is authenticated: no; Data was acquired via local or encrypted transport: no
-- Data from: cache
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemctl stop systemd-resolved
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemctl status systemd-resolved
○ systemd-resolved.service - Network Name Resolution
     Loaded: loaded (/usr/lib/systemd/system/systemd-resolved.service; disabled; vendor preset: enabled)
     Active: inactive (dead)
       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

Aug 08 13:01:50 1656943212 systemd-resolved[200152]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65d08458e880409bbc683457104237c7f8ec8d
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: Negative trust anchors: home.arpa 10.in-addr.arpa 16.172.in-addr.arpa 17.172.in-addr.arpa 18.172.in-ad>
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: Using system hostname '1656943212'.
Aug 08 13:01:50 1656943212 systemd[1]: Started systemd-resolved.service - Network Name Resolution.
Aug 08 13:01:50 1656943212 systemd-resolved[200152]: enp5s0: Bus client set DNS server list to: 2606:4700:4700::64, 2606:4700:4700::6400
Aug 08 13:01:52 1656943212 systemd-resolved[200152]: Using degraded feature set UDP instead of UDP+EDNS0 for DNS server 2606:4700:4700::64.
Aug 08 13:03:01 1656943212 systemd-resolved[200152]: Flushed all caches.
Aug 08 13:36:04 1656943212 systemd[1]: Stopping systemd-resolved.service - Network Name Resolution...
Aug 08 13:36:04 1656943212 systemd[1]: systemd-resolved.service: Deactivated successfully.
Aug 08 13:36:04 1656943212 systemd[1]: Stopped systemd-resolved.service - Network Name Resolution.
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ nslookup reddit.com
;; connection timed out; no servers could be reached
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig reddit.com

; <<>> DiG 9.16.31-RH <<>> reddit.com
;; global options: +cmd
;; connection timed out; no servers could be reached
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig @127.0.0.53 reddit.com

; <<>> DiG 9.16.31-RH <<>> @127.0.0.53 reddit.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig @1.1.1.1 reddit.com

; <<>> DiG 9.16.31-RH <<>> @1.1.1.1 reddit.com
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ resolvectl query reddit.com
reddit.com: resolve call failed: Could not activate remote peer: activation request failed: unknown unit.
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$

I expected that this was merely because it was acquiring the addresses from the cache, which most of the commands appear to be, but ping and dnf operate!

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ping reddit.com
PING reddit.com(2a04:4e42:600::396 (2a04:4e42:600::396)) 56 data bytes
64 bytes from 2a04:4e42:600::396 (2a04:4e42:600::396): icmp_seq=1 ttl=60 time=17.2 ms
^C64 bytes from 2a04:4e42:600::396: icmp_seq=2 ttl=60 time=39.4 ms

--- reddit.com ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 17.180/28.293/39.406/11.113 ms
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ping 2a04:4e42:600::396
PING 2a04:4e42:600::396(2a04:4e42:600::396) 56 data bytes
64 bytes from 2a04:4e42:600::396: icmp_seq=1 ttl=60 time=66.1 ms
64 bytes from 2a04:4e42:600::396: icmp_seq=2 ttl=60 time=18.3 ms
^C
--- 2a04:4e42:600::396 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 18.341/42.224/66.108/23.883 ms
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ su -c 'dnf upgrade --refresh --assumeyes; dnf repolist'
Cloudflare CentOS Packages                                                                                                  1.2 kB/s | 3.3 kB     00:02    
Errors during downloading metadata for repository 'cloudflare':
  - Status code: 404 for https://pkg.cloudflareclient.com/dists/36/main/binary-x86_64/repodata/repomd.xml (IP: 2606:4700:440e::6812:2fea)
Error: Failed to download metadata for repo 'cloudflare': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried
Fedora 36 - x86_64                                                                                                           52 kB/s |  20 kB     00:00    
Fedora 36 - x86_64 - Debug                                                                                                  103 kB/s |  18 kB     00:00    
Fedora 36 - Source                                                                                                          109 kB/s |  17 kB     00:00    
Fedora 36 openh264 (From Cisco) - x86_64                                                                                     10 kB/s | 989  B     00:00    
Fedora 36 openh264 (From Cisco) - x86_64 - Debug                                                                            6.9 kB/s | 997  B     00:00    
Fedora Modular 36 - x86_64                                                                                                  158 kB/s |  20 kB     00:00    
Fedora Modular 36 - x86_64 - Debug                                                                                          137 kB/s |  17 kB     00:00    
Fedora Modular 36 - Source                                                                                                   93 kB/s |  17 kB     00:00    
Fedora 36 - x86_64 - Updates                                                                                                183 kB/s |  17 kB     00:00    
Fedora 36 - x86_64 - Updates - Debug                                                                                        159 kB/s |  15 kB     00:00    
Fedora 36 - Updates Source                                                                                                   98 kB/s |  15 kB     00:00    
Fedora Modular 36 - x86_64 - Updates                                                                                        166 kB/s |  18 kB     00:00    
Fedora Modular 36 - x86_64 - Updates - Debug                                                                                 92 kB/s |  17 kB     00:00    
Fedora Modular 36 - Updates Source                                                                                          175 kB/s |  17 kB     00:00    
Fedora 36 - x86_64 - Test Updates                                                                                           122 kB/s |  16 kB     00:00    
Fedora 36 - x86_64 - Test Updates Debug                                                                                      82 kB/s |  15 kB     00:00    
Fedora 36 - Test Updates Source                                                                                              98 kB/s |  14 kB     00:00    
Fedora Modular 36 - x86_64 - Test Updates                                                                                   134 kB/s |  17 kB     00:00    
Fedora Modular 36 - x86_64 - Test Updates Debug                                                                             117 kB/s |  16 kB     00:00    
Fedora Modular 36 - Test Updates Source                                                                                     132 kB/s |  16 kB     00:00    
Darktable (Fedora_36)                                                                                                       4.4 kB/s | 1.7 kB     00:00    
packages-microsoft-com-prod                                                                                                 0.0  B/s |   0  B     00:00    
Errors during downloading metadata for repository 'packages-microsoft-com-prod':
  - Curl error (7): Couldn't connect to server for https://packages.microsoft.com/rhel/8/prod/repodata/repomd.xml []
Error: Failed to download metadata for repo 'packages-microsoft-com-prod': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried
ProtonVPN Fedora Stable repository                                                                                          969  B/s | 659  B     00:00    
RPM Fusion for Fedora 36 - Free                                                                                              33 kB/s | 7.8 kB     00:00    
RPM Fusion for Fedora 36 - Free tainted                                                                                      44 kB/s | 7.1 kB     00:00    
RPM Fusion for Fedora 36 - Free - Updates                                                                                    47 kB/s | 7.0 kB     00:00    
RPM Fusion for Fedora 36 - Nonfree                                                                                           52 kB/s | 7.9 kB     00:00    
RPM Fusion for Fedora 36 - Nonfree tainted                                                                                   47 kB/s | 7.1 kB     00:00    
RPM Fusion for Fedora 36 - Nonfree - Updates                                                                                 47 kB/s | 7.1 kB     00:00    
Ignoring repositories: cloudflare, packages-microsoft-com-prod
Dependencies resolved.
============================================================================================================================================================
 Package                           Architecture                     Version                                 Repository                                 Size
============================================================================================================================================================
Upgrading:
 libwebp                           i686                             1.2.4-1.fc36                            updates-testing                           290 k
 libwebp                           x86_64                           1.2.4-1.fc36                            updates-testing                           278 k

Transaction Summary
============================================================================================================================================================
Upgrade  2 Packages

Total download size: 567 k
Downloading Packages:
(1/2): libwebp-1.2.4-1.fc36.x86_64.rpm                                                                                      793 kB/s | 278 kB     00:00    
(2/2): libwebp-1.2.4-1.fc36.i686.rpm                                                                                        807 kB/s | 290 kB     00:00    
------------------------------------------------------------------------------------------------------------------------------------------------------------
Total                                                                                                                       1.1 MB/s | 567 kB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                                                                    1/1 
  Upgrading        : libwebp-1.2.4-1.fc36.x86_64                                                                                                        1/4 
  Upgrading        : libwebp-1.2.4-1.fc36.i686                                                                                                          2/4 
  Cleanup          : libwebp-1.2.3-1.fc36.i686                                                                                                          3/4 
  Cleanup          : libwebp-1.2.3-1.fc36.x86_64                                                                                                        4/4 
  Running scriptlet: libwebp-1.2.3-1.fc36.x86_64                                                                                                        4/4 
  Verifying        : libwebp-1.2.4-1.fc36.i686                                                                                                          1/4 
  Verifying        : libwebp-1.2.3-1.fc36.i686                                                                                                          2/4 
  Verifying        : libwebp-1.2.4-1.fc36.x86_64                                                                                                        3/4 
  Verifying        : libwebp-1.2.3-1.fc36.x86_64                                                                                                        4/4 

Upgraded:
  libwebp-1.2.4-1.fc36.i686                                                   libwebp-1.2.4-1.fc36.x86_64                                                  

Complete!
repo id                                                                repo name
cloudflare                                                             Cloudflare CentOS Packages
fedora                                                                 Fedora 36 - x86_64
fedora-cisco-openh264                                                  Fedora 36 openh264 (From Cisco) - x86_64
fedora-cisco-openh264-debuginfo                                        Fedora 36 openh264 (From Cisco) - x86_64 - Debug
fedora-debuginfo                                                       Fedora 36 - x86_64 - Debug
fedora-modular                                                         Fedora Modular 36 - x86_64
fedora-modular-debuginfo                                               Fedora Modular 36 - x86_64 - Debug
fedora-modular-source                                                  Fedora Modular 36 - Source
fedora-source                                                          Fedora 36 - Source
graphics_darktable                                                     Darktable (Fedora_36)
packages-microsoft-com-prod                                            packages-microsoft-com-prod
protonvpn-fedora-stable                                                ProtonVPN Fedora Stable repository
rpmfusion-free                                                         RPM Fusion for Fedora 36 - Free
rpmfusion-free-tainted                                                 RPM Fusion for Fedora 36 - Free tainted
rpmfusion-free-updates                                                 RPM Fusion for Fedora 36 - Free - Updates
rpmfusion-nonfree                                                      RPM Fusion for Fedora 36 - Nonfree
rpmfusion-nonfree-tainted                                              RPM Fusion for Fedora 36 - Nonfree tainted
rpmfusion-nonfree-updates                                              RPM Fusion for Fedora 36 - Nonfree - Updates
updates                                                                Fedora 36 - x86_64 - Updates
updates-debuginfo                                                      Fedora 36 - x86_64 - Updates - Debug
updates-modular                                                        Fedora Modular 36 - x86_64 - Updates
updates-modular-debuginfo                                              Fedora Modular 36 - x86_64 - Updates - Debug
updates-modular-source                                                 Fedora Modular 36 - Updates Source
updates-source                                                         Fedora 36 - Updates Source
updates-testing                                                        Fedora 36 - x86_64 - Test Updates
updates-testing-debuginfo                                              Fedora 36 - x86_64 - Test Updates Debug
updates-testing-modular                                                Fedora Modular 36 - x86_64 - Test Updates
updates-testing-modular-debuginfo                                      Fedora Modular 36 - x86_64 - Test Updates Debug
updates-testing-modular-source                                         Fedora Modular 36 - Test Updates Source
updates-testing-source                                                 Fedora 36 - Test Updates Source
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$

Additionally, clearing the cache appears to not impact anything.

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemd-resolve --statistics
DNSSEC supported by current servers: no

Transactions            
Current Transactions: 0
  Total Transactions: 23
                        
Cache                   
  Current Cache Size: 8
          Cache Hits: 3
        Cache Misses: 25
                        
DNSSEC Verdicts         
              Secure: 0
            Insecure: 0
               Bogus: 0
       Indeterminate: 0
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig reddit.com

; <<>> DiG 9.16.31-RH <<>> reddit.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 36922
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;reddit.com.                    IN      A

;; ANSWER SECTION:
reddit.com.             276     IN      A       151.101.65.140
reddit.com.             276     IN      A       151.101.193.140
reddit.com.             276     IN      A       151.101.129.140
reddit.com.             276     IN      A       151.101.1.140

;; Query time: 1 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Aug 08 13:46:43 BST 2022
;; MSG SIZE  rcvd: 103

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ resolvectl flush-caches
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ systemd-resolve --statistics
DNSSEC supported by current servers: no

Transactions            
Current Transactions: 0
  Total Transactions: 24
                        
Cache                   
  Current Cache Size: 0
          Cache Hits: 4
        Cache Misses: 25
                        
DNSSEC Verdicts         
              Secure: 0
            Insecure: 0
               Bogus: 0
       Indeterminate: 0
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ dig reddit.com

; <<>> DiG 9.16.31-RH <<>> reddit.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29843
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 65494
;; QUESTION SECTION:
;reddit.com.                    IN      A

;; ANSWER SECTION:
reddit.com.             264     IN      A       151.101.1.140
reddit.com.             264     IN      A       151.101.193.140
reddit.com.             264     IN      A       151.101.129.140
reddit.com.             264     IN      A       151.101.65.140

;; Query time: 11 msec
;; SERVER: 127.0.0.53#53(127.0.0.53)
;; WHEN: Mon Aug 08 13:46:57 BST 2022
;; MSG SIZE  rcvd: 103

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$

Lastly, I attempted to connect via the drive that mediawriter created for my some months ago. It is unable to connect.

I recall that when I used to utilize Windows, I was able to remediate any lack of connectivity via the Network Troubleshooter. Yes, it does actually work for some people. I recall that it used to either remediate an incorrectly configured, or mismatched, Internet Protocol address, or an unspecified Domain Name System error. I have attempted to remediate my potential Domain Name System problemage to no avail, but what might the previous thing refer to?

Despite all of this, telegram-desktop operates without problem: I receive and send messages constantly. However, steam is unable to operate. This mirrors how I am unable to access “https://store.steampowered.com/” via firefox (and chromium-browser, with it providing “ERR_NAME_NOT_RESOLVED”) yet am able to access “https://telegram.org/” (and “google.com”, in order to locate the websites to access, because I do not recall the Uniform Resource Identifier of every page that I access).

What is possibly able to cause such unusual problemage? I am utterly unable to ascertain it, and remarkably confused. I ask via this forum rather than Sky’s because although my other devices are occasionally unable to connect, none of them experience the problem that this computer does, much less as reproducibly.

1 Like

Do you have nscd installed? If so, you should probably uninstall that. It is deprecated since Fedora Linux switched to systemd-resolved.

Also, you might want to check that the hosts line in /etc/nsswitch.conf contains resolve and not dns since you indicate that you are using systemd-resolved for name services.

2 Likes

@glb, I have never touched this stuff before this problem arose, since this installation is very new; it is probably 1 month old.

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ nscd
bash: nscd: command not found...

nscd appears to not exist. (I expect consequently.)

However, of

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ cat /etc/nsswitch.conf 
# Generated by authselect on Mon Jul  4 17:13:26 2022
# Do not modify this file manually, use authselect instead. Any user changes will be overwritten.
# You can stop authselect from managing your configuration by calling 'authselect opt-out'.
# See authselect(8) for more details.

# In order of likelihood of use to accelerate lookup.
passwd:     files sss systemd
shadow:     files
group:      files sss systemd
hosts:      files myhostname mdns4_minimal [NOTFOUND=return] resolve [!UNAVAIL=return] dns
services:   files sss
netgroup:   files sss
automount:  files sss

aliases:    files
ethers:     files
gshadow:    files
networks:   files dns
protocols:  files
publickey:  files
rpc:        files

hosts: files myhostname mdns4_minimal [NOTFOUND=return] resolve [!UNAVAIL=return] dns” demonstrates that the 2nd thing that you mention is correct. Are you able to inform me of how to utilize authselect to modify the file how you describe?

authselect will always put dns at the end of the hosts line.
Just leave it as is. Most Fedora systems has the exact same setting.

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Do you by any chance have DNS-over-HTTPS enabled in Firefox?

https://support.mozilla.org/en-US/kb/dns-over-https-doh-faqs

@vekruse, I have evaluated whether that affects anything. It does not appear to. However, it might have been enabled when I invoked some of the commands that are included within the original post.

It is because 192.168.0.1 is not a “name”. It is an IP address. DNS is not used if the IP address is supplied directly.

From the output of the dig and nslookup commands you provided, it looks like your DNS services are working OK.

It is possible that something earlier on that hosts line is returning a bad result. For example, do you have an entry for reddit.com in your /etc/hosts file? The /etc/hosts file corresponds to the files entry on the hosts line in /etc/nsswitch.conf. Things listed in /etc/hosts will overrule other services listed later on that line in /etc/nsswitch.

Edit: I just realized that you said you cannot access “http://192.168.0.1”. In that case, you probably have a routing problem of some sort. You might want to inspect the output of ip route and see if IP traffic is being routed the wrong way for certain destinations.

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@glb, ip route outputs nothing:

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ip route
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$

Additionally, although probably irrelevant, as your most recent modification to your post suggests,

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ cat /etc/hosts 
# Loopback entries; do not change.
# For historical reasons, localhost precedes localhost.localdomain:
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
# See hosts(5) for proper format and other examples:
# 192.168.1.10 foo.mydomain.org foo
# 192.168.1.13 bar.mydomain.org bar
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$

demonstrates that “file://localhost/etc/hosts” does not contain anything except template-entries.

While this is not directly related to the question I wonder why I see [BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ as your user prompt.
From the beginning in *nix and as far as I know still today with linux a username has always been required to begin with a lower case letter and is normally all lowercase. The default user prompt in fedora is normally username@hostname so seeing all caps like that is a bit disconcerting.

As far as not connecting to some parts of the internet, there are 2 very possible factors and both are related to the IP mode in use.

I see that you have both IPv4 and IPv6 enabled in dns. I suspect that your ISP and/or other parts of your direct path to the internet do not properly support IPv6 (either direct addressing or dns). A router that does not support IPv6 addressing will often simply fail when trying to access an IPv6 address via that path. I have IPv4 only enabled and to date have not encountered any situations where I was not able to access an internet site. I think that ALL will support IPv4 addressing but to date only SOME support IPv6.

My suggestion for troubleshooting is to disable IPv6 on your system, including removing your nameserver data you have configured for IPv6 and try that to see if it solves the issue.

As far as reaching your router at 192.168.0.1;
With chrome I have to use http://192.168.0.1 in the address bar to access the web interface to my router. Using 192.168.0.1 and expecting it to connect simply fails. I think that part is the browser attempting to use https and dns, and not the address or LAN because as soon as I add the http:// at the beginning it works.

It actually looks like your problem might be the other way around – your computer might have routes for IPv6 traffic, but not for IPv4. This is not a configuration that I am familiar with. But does ip -6 route show anything? If so, and you truly have no IPv4 routes, then I guess you would need to instruct your DNS clients to only return IPv6 addresses or you need to configure some IPv4 routes. I’m quite sure that not all internet sites are available via IPv6 yet. So you probably want to configure some IPv4 routes. You probably just need to set an IPv4 gateway in your networking configuration. If you are using DHCP, you may need to enable IPv4 on your router.

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@computersavvy, I configured my username at install-time via the normal interface. Behind the hood, it may utilize the --badname flag. However, this should not be problematic for most well-designed software, especially cross-platform software (because it must deal with Windows usernames, which frequently contain upper-case characters).

Anyway, attempting to access “http://192.168.0.1” via chromium-browser provides

This site can’t be reached
http://192.168.0.1/ is unreachable.
ERR_ADDRESS_UNREACHABLE

Please know that none of these problems afflicted me until I reinitialized (to apply an update) but this problem now affects my installation-media and previous kernels too.

@glb, that was what I hypothesized based upon how the output of everything except the DNS cache returns IPv6 addresses. And, indeed, ip -6 route returns:

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ip -6 route
::1 dev lo proto kernel metric 256 pref medium
2a02:c7f:510c:9f00::/64 dev enp5s0 proto ra metric 100 pref medium
fd60:b525:84eb::/64 dev enp5s0 proto ra metric 100 pref medium
fe80::/64 dev enp5s0 proto kernel metric 1024 pref medium
default via fe80::a2bd:cdff:fe95:dd9 dev enp5s0 proto ra metric 100 pref medium

How am I to provide myself an IPv4 address?

Neither have I. Unfortunately, I switched to using systemd-networkd a while back and I’m not sure how to properly configure NetworkManager either.

However, if you know that 192.168.0.1 is the address of your router, I think the following command would add that as a non-persistent route (it won’t stay if you reboot your PC).

ip route add default via 192.168.0.1 dev enp5s0

(I took the device name from the default route for your IPv6 traffic.)

Does that require sudo/su to invoke?

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ip route add default via 192.168.0.1 dev enp5s0
RTNETLINK answers: Operation not permitted

Don’t wanna do anything that might corrupt my config, so checking.

Additionally, what does that do? — allow me to connect to the IP address?

Yes. It basically just says “for any IPv4 traffic, throw it out the enp5s0 device and at “192.168.0.1” and hope that that will take it from there”. :slightly_smiling_face:

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[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ sudo ip route add default via 192.168.0.1 dev enp5s0
Error: Nexthop has invalid gateway.

Eek.

Oh. I guess it wants 192.168.0.1 to be resolvable first. Normally, you would add that as a “gateway” on your network device. It should be possible to do it from the command-line as a one-off command, but I guess I’ve forgotten how to do that. You can see if it “took” by running ip route and you can remove the rule by running the same rule but substituting “add” with “delete”. I’ll have to look up how to do it from the command line now.

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ ip route
[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ sudo ip route remove default via 192.168.0.1 dev enp5s0
Command "remove" is unknown, try "ip route help".

I’ve never quite understood how to access the man-files for specific commands. Are you able to tell me how to access the manual for ip route? I am probably able to at least ascertain the correct verb myself.

That’s what I was just looking at. It is man ip-route. And at the very bottom of that file is basically the exact command that I gave you earlier.

Edit: Sorry, it’s ip route delete ... not ip route remove .... I don’t mess with ip routes that often. :slightly_smiling_face:

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Yeah, I just assumed that it would be separate. Apologies. man ip-route worked for me too. The verb appears to be del (although delete works too).

[BEEDELLROKEJULIANLOCKHART@1656943212 ~]$ sudo ip route del default via 192.168.0.1 dev enp5s0
RTNETLINK answers: No such process

Appears that it wasn’t taken.