atcoder.org - robtex.com
atcoder.org
| DNSSEC | ⚠️ Not signed | ||||||
| A | 54.65.172.3🇯🇵 Amazon54.64.0.0/15 EC2 NRT prefix | ||||||
| PTR | ec2-54-65-172-3.ap-northeast-1.compute.amazonaws.com | ||||||
| NS | ns1.value-domain.com ⭐ | ||||||
| A | 172.64.52.38🇺🇸 Cloudflare172.64.52.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| A | 172.64.52.161🇺🇸 Cloudflare172.64.52.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| NS | ns2.value-domain.com | ||||||
| A | 172.64.53.3🇺🇸 Cloudflare172.64.53.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| A | 172.64.53.115🇺🇸 Cloudflare172.64.53.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| SOA | ns1.value-domain.comhostmaster@atcoder.org 2020-08-26 #20 | ||||||
org
| DNSSEC | 🔒 Signed (DS record present) | ||||||
| NS | a0.org.afilias-nst.info ⭐ ⚠️ Not in parent delegation | ||||||
| NS | a2.org.afilias-nst.info ⚠️ Not in parent delegation | ||||||
| NS | b0.org.afilias-nst.org | ||||||
| NS | b2.org.afilias-nst.org | ||||||
| NS | c0.org.afilias-nst.info ⚠️ Not in parent delegation | ||||||
| NS | d0.org.afilias-nst.org | ||||||
| SOA | a0.org.afilias-nst.infohostmaster@donuts.email serial=1778347550 | ||||||
Same first word
Similar names
DNS History
5 records (3 active, 2 former)
●NSns1.value-domain.com2015-05-09 → 2026-05-09 · 2 obs
● 2026-05-09 17:47:22
●NSns2.value-domain.com2015-05-09 → 2026-05-09 · 2 obs
● 2026-05-09 17:47:22
○A119.245.243.942016-04-13 → 2017-06-15 · 5 obs
● 2016-04-13 11:48:14
● 2017-06-15 17:58:06
○ 2026-04-02 06:39:20
○ 2026-05-09 17:47:22
○A202.222.31.772015-05-09 → 2016-01-22 · 4 obs
● 2016-01-22 22:45:14
○ 2016-04-13 11:48:14
○ 2026-05-09 17:47:22
●A54.65.172.32026-04-02 → 2026-05-09 · 3 obs
● 2026-04-02 06:39:20
● 2026-05-09 17:47:22
🔍 DNS Trace
📋 Delegation Chain
| Zone | Nameservers | Glue |
|---|---|---|
| org | b2.org.afilias-nst.org, d0.org.afilias-nst.org, b0.org.afilias-nst.org | - |
| atcoder.org | ns2.value-domain.com, ns1.value-domain.com | - |
✅ Authoritative Response
Server:172.64.53.3
NS records: ns2.value-domain.com, ns1.value-domain.com
🔒 DNSSEC Status
⚠️ Insecure (no DNSSEC)
No DS record for atcoder.org (unsigned zone)
⏱️ Timing
Total: 642ms | Queries: -
📄 Records
| Type | Count | Sample Data |
|---|---|---|
| A | 1 | 54.65.172.3 |
| NS | 2 | ns1.value-domain.com, ns2.value-domain.com |
| SOA | 1 | ns1.value-domain.com hostmaster.atcoder. |
Analysis
IP Addresses
atcoder.org resolves to one IP number: 54.65.172.3.
Other host names, for instance relax-life.net, www.nine220volts.com, dianwww.hrwh.org, taomirin.com and preshare.net share IP numbers with atcoder.org.
Name Servers
atcoder.org's delegation uses two name servers: ns1.value-domain.com and ns2.value-domain.com.
atcoder.org uses the same name server setup as other domains, such as ytt.tokyo, naraspot.net, assist-one.net, wako-unyu.co.jp and sukitoku.jp.
atcoder.org at least partially shares name servers with other domains, including webdo.jp, top-sports.jp, kuraponex.org, j-cma.com and itdo.jp.
These name servers are commonly used with ns3.value-domain.com, ns4.value-domain.com, ns5.value-domain.com, ns11.value-domain.com, ns12.value-domain.com and ns13.value-domain.com.
Host names with two IPs:
ns1.value-domain.com points to 172.64.52.38 and 172.64.52.161
ns2.value-domain.com points to 172.64.53.3 and 172.64.53.115