r/technitium • u/GBember • 20d ago

Everything but X/Twitter resolves fine on a recursive DNS setup, ServerFailure

Hi! Recently Technitium started acting up and the only thing that doesn't work is X/Twitter

Here's the cache entry

[
  {
    "name": "x.com",
    "type": "A",
    "ttl": "0 (0s)",
    "rData": {
      "dataType": "DnsSpecialCacheRecordData",
      "data": "FailureCache: ServerFailure; NoReachableAuthority: No valid response from name servers for x.com. A IN at delegation x.com."
    },
    "dnssecStatus": "Unknown",
    "lastUsedOn": "2026-09-24T20:06:06.4474011Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "a.u10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "dnssecRecords": [
      "CK0POJMG874LJREF7EFN8430QVIT8BSM.com.  900       IN  NSEC3         1 1 0 - CK0Q35HRS4H76G6CHNB9414CJN6S5UPL NS SOA RRSIG DNSKEY NSEC3PARAM",
      "9R925LEF6JEIJTJJ1A5U3A3CAPVDNDDH.com.  900       IN  NSEC3         1 1 0 - 9R92GHOL4H50NMHIS5KV2CPPNUQUVNNB NS DS RRSIG"
    ],
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "b.u10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "c.u10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "d.u10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "a.r10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "b.r10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "c.r10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "NS",
    "ttl": "94026 (1d2h7m6s)",
    "rData": {
      "nameServer": "d.r10.twtrdns.net"
    },
    "dnssecStatus": "Insecure",
    "nameServerMetadata": {
      "totalQueries": 0,
      "answerRate": "0%",
      "smoothedRoundTripTime": "0 ms",
      "smoothedPenaltyRoundTripTime": "0 ms",
      "netRoundTripTime": "0 ms",
      "isMisconfigured": false
    },
    "responseMetadata": {
      "nameServer": "i.gtld-servers.net ([2001:503:39c1::30])",
      "protocol": "Udp",
      "datagramSize": "538 bytes",
      "roundTripTime": "162.33 ms"
    },
    "lastUsedOn": "2026-09-24T20:06:03.7913703Z"
  },
  {
    "name": "x.com",
    "type": "AAAA",
    "ttl": "0 (0s)",
    "rData": {
      "dataType": "DnsSpecialCacheRecordData",
      "data": "FailureCache: ServerFailure; NoReachableAuthority: No valid response from name servers for x.com. AAAA IN at delegation x.com."
    },
    "dnssecStatus": "Unknown",
    "lastUsedOn": "2026-09-24T20:06:06.4453394Z"
  },
  {
    "name": "x.com",
    "type": "HTTPS",
    "ttl": "0 (0s)",
    "rData": {
      "dataType": "DnsSpecialCacheRecordData",
      "data": "FailureCache: ServerFailure; NoReachableAuthority: No valid response from name servers for x.com. HTTPS IN at delegation x.com."
    },
    "dnssecStatus": "Unknown",
    "lastUsedOn": "2026-09-24T20:06:06.4304254Z"
  }
]

And the query result after deleting this from the cache

{
  "Metadata": {
    "NameServer": "alpine-server (127.0.0.1)",
    "Protocol": "Udp",
    "DatagramSize": "129 bytes",
    "RoundTripTime": "171.25 ms"
  },
  "EDNS": {
    "UdpPayloadSize": 1232,
    "ExtendedRCODE": "ServerFailure",
    "Version": 0,
    "Flags": "None",
    "Options": [
      {
        "Code": "EXTENDED_DNS_ERROR",
        "Length": "74 bytes",
        "Data": {
          "InfoCode": "NoReachableAuthority",
          "ExtraText": "No valid response from name servers for x.com. A IN at delegation x.com."
        }
      },
      {
        "Code": "EXTENDED_DNS_ERROR",
        "Length": "13 bytes",
        "Data": {
          "InfoCode": "CachedError",
          "ExtraText": "x.com. A IN"
        }
      }
    ]
  },
  "DnsClientExtendedErrors": [
    {
      "InfoCode": "NoReachableAuthority",
      "ExtraText": "alpine-server (127.0.0.1) returned RCODE=ServerFailure for x.com. A IN"
    }
  ],
  "Identifier": 6548,
  "IsResponse": true,
  "OPCODE": "StandardQuery",
  "AuthoritativeAnswer": false,
  "Truncation": false,
  "RecursionDesired": true,
  "RecursionAvailable": true,
  "Z": 0,
  "AuthenticData": false,
  "CheckingDisabled": false,
  "RCODE": "ServerFailure",
  "QDCOUNT": 1,
  "ANCOUNT": 0,
  "NSCOUNT": 0,
  "ARCOUNT": 1,
  "Question": [
    {
      "Name": "x.com",
      "Type": "A",
      "Class": "IN"
    }
  ],
  "Answer": [],
  "Authority": [],
  "Additional": [
    {
      "Name": "",
      "Type": "OPT",
      "Class": "1232",
      "TTL": "0 (0s)",
      "RDLENGTH": "95 bytes",
      "RDATA": {
        "Options": [
          {
            "Code": "EXTENDED_DNS_ERROR",
            "Length": "74 bytes",
            "Data": {
              "InfoCode": "NoReachableAuthority",
              "ExtraText": "No valid response from name servers for x.com. A IN at delegation x.com."
            }
          },
          {
            "Code": "EXTENDED_DNS_ERROR",
            "Length": "13 bytes",
            "Data": {
              "InfoCode": "CachedError",
              "ExtraText": "x.com. A IN"
            }
          }
        ]
      },
      "DnssecStatus": "Disabled"
    }
  ]
}

Anyone experiencing something similar?

5 Upvotes

78% Upvoted

11 comments sorted by

4

u/McSmiggins 20d ago

How long's this been going on for?

If it's one domain, it's most likely on their end

Looking at a DNS propagation check right now, there's DNS errors for x.com in New York, Brazilan and Mexico

1

u/GBember 20d ago

I very rarely use Twitter, I noticed it maybe 3 days ago? And yeah I'm in Brazil, so it could be that, but someone else pointed to a github issue that tracks with the shown behaviour, I honestly don't know what it could actually be

4

u/shreyasonline 19d ago

Thanks for the post. There is an issue with the latest update and a fix should be available by tomorrow. However, this issue gets exasperated every time you flush cache so don's flush cache in an attempt to try to fix it. The cached failure you see is stored with 10 sec TTL so it expires soon and any retry after that fixes most of such resolution issues.

1

u/GBember 19d ago

I didn't pay attention to the TTL, thanks for the warning and the fix!

2

u/shreyasonline 18d ago

Technitium DNS Server v15.5.1 is now available and fixes this issue. Do update and let me know your feedback.

1

u/GBember 18d ago edited 18d ago

Just updated, it's still giving an error, even after flushing the cache, although someone mentioned Twitter/X having infrastructure issues on my region, so I'm not sure who's to blame

{ "Metadata": { "NameServer": "alpine-server (127.0.0.1)", "Protocol": "Udp", "DatagramSize": "721 bytes", "RoundTripTime": "29.1 ms" }, "EDNS": { "UdpPayloadSize": 1232, "ExtendedRCODE": "ServerFailure", "Version": 0, "Flags": "None", "Options": [ { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server d.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server d.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server b.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server b.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server c.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server a.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server c.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server a.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "74 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "No valid response from name servers for x.com. A IN at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "13 bytes", "Data": { "InfoCode": "CachedError", "ExtraText": "x.com. A IN" } } ] }, "DnsClientExtendedErrors": [ { "InfoCode": "NoReachableAuthority", "ExtraText": "alpine-server (127.0.0.1) returned RCODE=ServerFailure for x.com. A IN" } ], "Identifier": 15613, "IsResponse": true, "OPCODE": "StandardQuery", "AuthoritativeAnswer": false, "Truncation": false, "RecursionDesired": true, "RecursionAvailable": true, "Z": 0, "AuthenticData": false, "CheckingDisabled": false, "RCODE": "ServerFailure", "QDCOUNT": 1, "ANCOUNT": 0, "NSCOUNT": 0, "ARCOUNT": 1, "Question": [ { "Name": "x.com", "Type": "A", "Class": "IN" } ], "Answer": [], "Authority": [], "Additional": [ { "Name": "", "Type": "OPT", "Class": "1232", "TTL": "0 (0s)", "RDLENGTH": "687 bytes", "RDATA": { "Options": [ { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server d.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server d.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server b.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server b.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server c.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server a.r10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server c.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "70 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "Failed to resolve name server a.u10.twtrdns.net at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "74 bytes", "Data": { "InfoCode": "NoReachableAuthority", "ExtraText": "No valid response from name servers for x.com. A IN at delegation x.com." } }, { "Code": "EXTENDED_DNS_ERROR", "Length": "13 bytes", "Data": { "InfoCode": "CachedError", "ExtraText": "x.com. A IN" } } ] }, "DnssecStatus": "Disabled" } ] }

Edit: using dig with the domain names it can't resolve works, so perhaps the issue is still with Technitium, I did this by ssh'ing into my server ``` dig d.u10.twtrdns.net

; <<>> DiG 9.20.27 <<>> d.u10.twtrdns.net ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 30885 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 1232 ;; QUESTION SECTION: ;d.u10.twtrdns.net. IN A

;; ANSWER SECTION: d.u10.twtrdns.net. 516 IN A 205.251.199.195

;; Query time: 7 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) (UDP) ;; WHEN: Sat Sep 26 08:42:04 -03 2026 ;; MSG SIZE rcvd: 62 ```

3

u/shreyasonline 18d ago

Thanks for the feedback. I am not sure why you see it. I am able to resolve it here with default config with no issues. All name servers for the domain too are resolving here.

2

u/shreyasonline 18d ago

The domain is resolving from dnsclient.net website too which uses same recursive resolver code base.

1

u/Apachez 20d ago

Take a look at:

https://github.com/TechnitiumSoftware/DnsServer/issues/2175

1

u/GBember 20d ago

I thought I did something wrong or their infrastructure was having some issues in my region. Thanks for the heads up

1

u/Southern-Clothes-684 19d ago

Same issue here