duc.work - dns.ninja

`duc.work`

DNSSEC	⚠️ Not signed
A	2606:4700:3033::6815:1ee6^{🇺🇸 Cloudflare2606:4700:3033::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	2606:4700:3033::ac43:adf6^{🇺🇸 Cloudflare2606:4700:3033::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	104.21.30.230^{Cloudflare104.21.16.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	172.67.173.246^{🇺🇸 Cloudflare172.67.160.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
NS	`hans.ns.cloudflare.com` ⭐
		A	2606:4700:58::adf5:3baf^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`hans.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c1af^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`hans.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:21af^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`hans.ns.cloudflare.com`
		A	108.162.193.175^{🇺🇸 Cloudflare108.162.193.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`hans.ns.cloudflare.com`
		A	172.64.33.175^{🇺🇸 Cloudflare172.64.33.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`hans.ns.cloudflare.com`
		A	173.245.59.175^{🇺🇸 Cloudflare173.245.59.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`hans.ns.cloudflare.com`
NS	`may.ns.cloudflare.com`
		A	2606:4700:50::adf5:3a87^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`may.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c087^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`may.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:2087^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`may.ns.cloudflare.com`
		A	108.162.192.135^{🇺🇸 Cloudflare108.162.192.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`may.ns.cloudflare.com`
		A	172.64.32.135^{🇺🇸 Cloudflare172.64.32.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`may.ns.cloudflare.com`
		A	173.245.58.135^{🇺🇸 Cloudflare173.245.58.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`may.ns.cloudflare.com`
MX	`mx1.larksuite.com` ⭐
		A	18.139.153.173^{🇸🇬 Amazon18.138.0.0/15 EC2 SIN prefix}
			PTR	`ec2-18-139-153-173.ap-southeast-1.compute.amazonaws.com`
MX	`mx2.larksuite.com`⁽⁵⁾
		A	18.139.153.173^{🇸🇬 Amazon18.138.0.0/15 EC2 SIN prefix}
			PTR	`ec2-18-139-153-173.ap-southeast-1.compute.amazonaws.com`
MX	`mx3.larksuite.com`⁽¹⁰⁾
		A	18.139.153.173^{🇸🇬 Amazon18.138.0.0/15 EC2 SIN prefix}
			PTR	`ec2-18-139-153-173.ap-southeast-1.compute.amazonaws.com`
		A	101.126.58.223^{🇨🇳 VOLCANO-ENGINE101.126.56.0/21 China Internet Network Information Center Floor1, Building No.1 C/-Chinese Academy of Sciences 4, South 4th Street Haidian District,}
		A	122.14.230.154^{🇨🇳 CHINAMOBILE-CN122.14.224.0/20}
TXT	`v=spf1 +include:spf.onlarksuite.com -all`
TXT	`verification-code-site-App_lark=sxHkrIjSRLJflU8oUK0m`
TXT	`verification-code-site-App_lark=wfoZf4e6Cha1zkAAQ1wQ`
HTTPS	HTTP/3, HTTP/2 ✓ hints match
		IPv4 hints	104.21.30.230, 172.67.173.246
		IPv6 hints	2606:4700:3033::6815:1ee6, 2606:4700:3033::ac43:adf6
		ECH	X25519, HKDF-SHA256 + AES-128-GCM draft, id=53, name=cloudflare-ech.com
SOA	`hans.ns.cloudflare.com`dns@cloudflare.com serial=2407626069

`work`

	DNSSEC	🔒 Signed (DS record present)
	NS	`a.nic.work` ⭐
	NS	`b.nic.work`
	NS	`c.nic.work`
	NS	`x.nic.work`
	NS	`y.nic.work`
	NS	`z.nic.work`
	SOA	`a.nic.work`admin@tldns.godaddy serial=1785526205

⚠️ On DNS blocklist: tif

Same first word

duc.ru

duc.com

duc.be

duc.com.ar

duc.fi

duc.co

duc.cc

duc.tech

duc.in

duc.com.kw

duc.edu.in

duc.com.br

duc.de

duc.ch

duc.net

duc.us

duc.do

duc.cn

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duc.biz

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duc.at

duc.si

duc.jp

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duc.com.mx

duc.edu.iq

duc.koeln

duc.co.uk

duc.co.za

duc.nl

duc.edu.gh

duc.ca

duc.one

duc.me

duc.kr

duc.es

duc.hu

duc.tf

duc.eu

duc.fr

duc.link

duc.dk

duc.ro

duc.nu

duc.edu.sd

duc.as

duc.se

Similar names

udc.us

cud.be

cdu.edu.pl

dcu.net

cdu.it

cdu.me

ucd.edu

udc.edu

cdu.expert

dcu.ca

cud.com.pl

dcu.cz

udc.lv

cdu.ie

udc.uz

udc.co

udc.kr

cud.no

dcu.ua

cdu.su

cdu.pl

ucd.ro

cdu.mil.lv

ucd.com.tw

udc.go.ug

cdu.gl

udc.net

udc.co.nz

ucd.ru

cdu.nrw

ucd.jp

ucd.be

ucd.pl

udc.ro

cdu.com.ph

udc.br

ucd.ch

cdu.ac.in

cdu.edu.ua

udc.es

udc.com.mx

cud.re.kr

dcu.kr

cdu.cz

udc.ie

cdu.events

udc.ru

cud.co.jp

dcu.co.za

udc.pt

dcu.ru

cud.com.mx

dcu.info

ucd.ie

ucd.money

udc.bg

cdu.one

udc.ch

udc.pl

cud.fr

udc.com

dcu.my

dcu.org.cn

ucd.at

cud.com.au

cdu.cn

cdu.eu

cdu.fr

cud.moda

cdu.watch

cud.io

cud.pl

cdu.nu

ucd.it

udc.edu.ar

udc.org.bw

cdu.al

udc.gal

cud.co

ucd.ac.ma

dcu.academy

udc.com.vn

udc.tv

udc.com.ua

DNS History

15 records (9 active, 6 former)

●NShans.ns.cloudflare.com2026-05-06 → 2026-07-31 · 2 obs

● 2026-05-06 18:30:40
● 2026-07-31 20:08:54

●NSmay.ns.cloudflare.com2026-05-06 → 2026-07-31 · 2 obs

● 2026-05-06 18:30:40
● 2026-07-31 20:08:54

●MXmx1.larksuite.com2026-05-06 → 2026-07-31 · 2 obs

● 2026-05-06 18:30:40
● 2026-07-31 20:08:54

●MXmx2.larksuite.com2026-05-06 → 2026-07-31 · 2 obs

● 2026-05-06 18:30:40
● 2026-07-31 20:08:54

●MXmx3.larksuite.com2026-05-06 → 2026-07-31 · 2 obs

● 2026-05-06 18:30:40
● 2026-07-31 20:08:54

●A104.21.30.2302026-05-06 → 2026-07-31 · 6 obs

● 2026-05-06 18:30:40
● 2026-06-16 02:22:36
○ 2026-06-18 21:08:54
● 2026-07-19 10:35:30
○ 2026-07-30 05:09:38
● 2026-07-31 20:08:54

●A172.67.173.2462026-05-06 → 2026-07-31 · 6 obs

● 2026-05-06 18:30:40
● 2026-06-16 02:22:36
○ 2026-06-18 21:08:54
● 2026-07-19 10:35:30
○ 2026-07-30 05:09:38
● 2026-07-31 20:08:54

○A188.114.96.02026-06-18 → 2026-07-30 · 5 obs

○ 2026-06-16 02:22:36
● 2026-06-18 21:08:54
○ 2026-07-19 10:35:30
● 2026-07-30 05:09:38
○ 2026-07-31 20:08:54

○A188.114.97.02026-06-18 → 2026-07-30 · 5 obs

○ 2026-06-16 02:22:36
● 2026-06-18 21:08:54
○ 2026-07-19 10:35:30
● 2026-07-30 05:09:38
○ 2026-07-31 20:08:54

○A2606:4700:3030::6815:1ee62026-05-06 → 2026-06-16 · 4 obs

● 2026-05-06 18:30:40
● 2026-06-16 02:22:36
○ 2026-06-18 21:08:54
○ 2026-07-31 20:08:54

○A2606:4700:3031::ac43:adf62026-05-06 → 2026-06-16 · 4 obs

● 2026-05-06 18:30:40
● 2026-06-16 02:22:36
○ 2026-06-18 21:08:54
○ 2026-07-31 20:08:54

●A2606:4700:3033::6815:1ee62026-07-19 → 2026-07-31 · 4 obs

○ 2026-06-18 21:08:54
● 2026-07-19 10:35:30
○ 2026-07-30 05:09:38
● 2026-07-31 20:08:54

●A2606:4700:3033::ac43:adf62026-07-19 → 2026-07-31 · 4 obs

○ 2026-06-18 21:08:54
● 2026-07-19 10:35:30
○ 2026-07-30 05:09:38
● 2026-07-31 20:08:54

○A2a06:98c1:3120::2026-06-18 → 2026-07-30 · 5 obs

○ 2026-06-16 02:22:36
● 2026-06-18 21:08:54
○ 2026-07-19 10:35:30
● 2026-07-30 05:09:38
○ 2026-07-31 20:08:54

○A2a06:98c1:3121::2026-06-18 → 2026-07-30 · 5 obs

○ 2026-06-16 02:22:36
● 2026-06-18 21:08:54
○ 2026-07-19 10:35:30
● 2026-07-30 05:09:38
○ 2026-07-31 20:08:54

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
work	a.nic.work, b.nic.work, c.nic.work, x.nic.work...	12 records
duc.work	hans.ns.cloudflare.com, may.ns.cloudflare.com	-

✅ Authoritative Response

Server:172.64.32.135

NS records: hans.ns.cloudflare.com, may.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for duc.work (unsigned zone)

⏱️ Timing

Total: 1302ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`172.67.173.246, 104.21.30.230`
AAAA	2	`2606:4700:3033::6815:1ee6, 2606:4700:3033::ac43:adf6`
NS	2	`hans.ns.cloudflare.com, may.ns.cloudflare.com`
MX	3	`mx1.larksuite.com (pri: 1), mx3.larksuite.com (pri: 10)...`
TXT	3	`v=spf1 +include:spf.onlarksuite.com -all, verification-code-site-App_lark=sxHkrIjS...`
HTTPS	1	`{"priority":1,"target":".","alpn":["h3",`
SOA	1	`hans.ns.cloudflare.com dns.cloudflare.co`

📌 Glue Records Collected

Total: 12

In-bailiwick: 12 (a.nic.work, a.nic.work, b.nic.work...)

Analysis

IP Addresses

duc.work directs to four IP numbers, which are 104.21.30.230, 172.67.173.246, 2606:4700:3033::6815:1ee6 and 2606:4700:3033::ac43:adf6.

yaesu.com.tw, chok.pl, hoogland.co.za plus two other host names have IP numbers in common with duc.work.

Name Servers

duc.work is delegated to two name servers: hans.ns.cloudflare.com and may.ns.cloudflare.com.

The name server configuration of duc.work is shared with other domains, for instance aqdm527.com, aqdm514.com, freedreams.org and two others.

There is at least partial name server overlap between duc.work and other domains — returntobasis.com, 01299.cfd, shivampaw.com and two more among them.

These name servers are routinely deployed together with the name servers brenda.ns.cloudflare.com.

Hosts with 6 IP addresses each:

hans.ns.cloudflare.com resolves to 108.162.193.175, 172.64.33.175, 173.245.59.175 and 3 other IP addresses.

may.ns.cloudflare.com resolves to 108.162.192.135, 172.64.32.135, 173.245.58.135 and 3 other IP addresses.

Mail Servers

Incoming mail for duc.work is delivered via three mail servers: mx1.larksuite.com, mx2.larksuite.com and mx3.larksuite.com.

At least some of the mail servers used by duc.work are shared with other domains: synertec.org, metech.com.vn, wenfu.cn and two others among them.

Host names carrying three IP numbers:

mx3.larksuite.com points to 18.139.153.173, 101.126.58.223 and 122.14.230.154.

Host names resolving to a single IP address:

mx1.larksuite.com points to 18.139.153.173.

mx2.larksuite.com points to 18.139.153.173.

Three host names point to 18.139.153.173: mx3.larksuite.com, mx1.larksuite.com and mx2.larksuite.com.