The ultralow SGN server is not connected?

Hi,

Starting yesterday, I noticed that the ultralow SGN servers are still active, but IP address records aren't returning these SGN servers. Are the authoritative DNS servers updating their databases with new IP address locations, or is there some kind of error causing the identification of IPs near the ultralow servers?

This is the output from the Viettel network:

{
    "status": "ok",
    "protocol": "DOH",
    "client": "115.73.144.XXX",
    "srcIP": "115.73.144.XXX",
    "destIP": "38.54.31.178",
    "anycast": false,
    "server": "lightnode-han-1",
    "clientName": "chromium-default"
}

  lightnode-sgn                     6 ms
  viettel-sgn                       7 ms
  viettel-sgn (IPv6)                7 ms
  viettel-han                      27 ms  (ultralow2)
■ lightnode-han                    28 ms  (ultralow1)
  vultr-sin                        35 ms
  vultr-sin (IPv6)                 35 ms
  zepto-sin (IPv6)                 37 ms
  zepto-sin                        42 ms
  lightnode-kul                    60 ms
  zepto-tpe                        62 ms  (anycast2)
  zepto-tpe (IPv6)                 63 ms  (anycast2)
  bangmod-bkk                      69 ms
  lightnode-bkk                    74 ms
  anexia-kul                      177 ms
  anexia-kul (IPv6)               218 ms
  viettel-han (IPv6)               error
  anycast.dns1.nextdns.io          error  (anycast1)
  anycast.dns1.nextdns.io (IPv6)   error  (anycast1)
  dns1.nextdns.io (IPv6)           error  (ultralow1)
  dns2.nextdns.io (IPv6)           error  (ultralow2)

Diag: https://nextdns.io/diag/fde1bcc0-64af-11f1-abcc-319bd3543af5

{
    "status": "ok",
    "protocol": "DOH",
    "client": "171.249.19.XXX",
    "srcIP": "171.249.19.XXX",
    "destIP": "38.54.31.178",
    "anycast": false,
    "server": "lightnode-han-1",
    "clientName": "trr"
}

  viettel-sgn (IPv6)                7 ms
  lightnode-sgn                     7 ms
  viettel-sgn                       7 ms
  viettel-han                      25 ms  (ultralow2)
■ lightnode-han                    26 ms  (ultralow1)
  vultr-sin (IPv6)                 35 ms
  vultr-sin                        36 ms
  anexia-sin                       36 ms
  lightnode-kul                    49 ms
  zepto-tpe                        61 ms  (anycast2)
  bangmod-bkk                      72 ms
  lightnode-bkk                    77 ms
  anexia-kul                      176 ms
  anexia-sin (IPv6)               202 ms
  anexia-kul (IPv6)               218 ms
  zepto-tpe (IPv6)                224 ms  (anycast2)
  viettel-han (IPv6)               error
  anycast.dns1.nextdns.io          error  (anycast1)
  anycast.dns1.nextdns.io (IPv6)   error  (anycast1)
  dns1.nextdns.io (IPv6)           error  (ultralow1)
  dns2.nextdns.io (IPv6)           error  (ultralow2)

Diag: https://nextdns.io/diag/b1905fd0-653f-11f1-9ba7-8db07155eeb7

The IP addresses in Can Tho and Kien Giang are located near the SGN server (based on ping), but are currently connecting to the HAN server. Here are the IP location results (from Maxmind):

I tried querying public DNS servers with ECS (such as OpenDNS/Quad9 ECS/Google DNS), and they all returned the same HAN server IP record. This is the `dns.nextdns.io` record with the authoritative DNS servers:

; <<>> DiG 9.17.15 <<>> dns.nextdns.io @ns1.nextdns.io
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32372
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;dns.nextdns.io.                        IN      A
;; ANSWER SECTION:
dns.nextdns.io.         298     IN      CNAME   steering.nextdns.io.
steering.nextdns.io.    60      IN      A       38.54.31.178
steering.nextdns.io.    60      IN      A       171.244.57.202
;; Query time: 34 msec
;; SERVER: 45.90.28.1#53(ns1.nextdns.io) (UDP)
;; WHEN: Thu Jun 11 13:48:50 SE Asia Standard Time 2026
;; MSG SIZE  rcvd: 160

; <<>> DiG 9.17.15 <<>> dns.nextdns.io @ns2.nextdns.io
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62582
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;dns.nextdns.io.                        IN      A
;; ANSWER SECTION:
dns.nextdns.io.         281     IN      CNAME   steering.nextdns.io.
steering.nextdns.io.    60      IN      A       38.54.31.178
steering.nextdns.io.    60      IN      A       171.244.57.202
;; Query time: 69 msec
;; SERVER: 45.90.30.1#53(ns2.nextdns.io) (UDP)
;; WHEN: Thu Jun 11 13:49:17 SE Asia Standard Time 2026
;; MSG SIZE  rcvd: 160

I asked friends at other network providers (VNPT, FPT, Viettel) to provide additional output:

* Viettel

* VNPT

* FPT 

Hopefully, this issue will be fixed soon.

Thank you!