tudou.com

Checked 22 October 2026, 11:13 UTC · via 8.8.8.8
✗Problems found
24 passed 1 warning 1 failed 5 info

Registration

info

.com generic · Alibaba Cloud Computing (Beijing) Co., Ltd. · expires 2027-07-13

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
Alibaba Cloud Computing (Beijing) Co., Ltd.
Registered
13 July 2004
Last changed
10 March 2026
Expires
13 July 2027
Status
client transfer prohibited
Registry nameservers
dns1.youku.com, dns2.youku.com, dns3.youku.com, dns4.youku.com
RDAP server
https://rdap.verisign.com/com/v1/

Checks

  • i
    .com is a generic TLD (gTLD)
    Generic TLD under an ICANN registry agreement: ICANN-accredited registrars, UDRP and RDAP apply.
    #1
  • ✓ TLD delegated and signed #2
    .com is delegated in the root zone and DNSSEC-signed.
  • ✓ Expires on 2027-07-13 #3
    The registration is valid until 2027-07-13 (263 days).
  • ✓ Transfer locked #4
    Registry status: client transfer prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

dns1.youku.com, dns2.youku.com, dns3.youku.com, dns4.youku.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
dns1.youku.com, dns2.youku.com, dns3.youku.com, dns4.youku.com
NS in the zone
dns1.youku.com, dns2.youku.com, dns3.youku.com, dns4.youku.com
NameserverAddressesNetwork (AS)Glue
dns1.youku.com140.205.103.193 2401:b180:4100::3AS37963 ALIBABA-CN-NET - Hangzhou Alibaba Advertising Co.,Ltd., CN AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN140.205.103.193 2401:b180:4100::3
dns2.youku.com106.11.41.145 106.11.35.17 2401:b180:4100::8AS37963 ALIBABA-CN-NET - Hangzhou Alibaba Advertising Co.,Ltd., CN AS37963 ALIBABA-CN-NET - Hangzhou Alibaba Advertising Co.,Ltd., CN AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN106.11.35.17 106.11.41.145 2401:b180:4100::8
dns3.youku.com47.88.74.37 47.241.207.17 2401:b180:4100::9AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN2401:b180:4100::9 47.241.207.17 47.88.74.37
dns4.youku.com140.205.122.88 2401:b180:4100::10AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN AS45102 ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN140.205.122.88 2401:b180:4100::10

Checks

  • ✓ 4 nameservers #6
    Delegated to dns1.youku.com, dns2.youku.com, dns3.youku.com, dns4.youku.com.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ No glue needed #8
    All nameservers are outside the zone, so no glue records are needed.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • i
    One address family in one network
    all IPv6 addresses are in 2401:b180:4100::/48, while the other address family is spread over several networks.
    #10
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS37963 (ALIBABA-CN-NET - Hangzhou Alibaba Advertising Co.,Ltd., CN): 3 addresses; AS45102 (ALIBABA-CN-NET - Alibaba (US) Technology Co., Ltd., CN): 7 addresses.
  • i
    All nameserver names under .com
    All nameserver names are under one TLD, so a problem with that TLD also makes the nameservers unreachable. Some operators use names under two TLDs for extra resilience.
    #12
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

fail

8 of 10 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns1.youku.com 140.205.103.193NOERROR, 193 ms, authoritativenoyes / yesrefused-
dns1.youku.com 2401:b180:4100::3NOERROR, 185 ms, authoritativenoyes / yesrefused-
dns2.youku.com 106.11.41.145no responsenono / no--
dns2.youku.com 106.11.35.17no responsenono / no--
dns2.youku.com 2401:b180:4100::8NOERROR, 203 ms, authoritativenoyes / yesrefused-
dns3.youku.com 47.88.74.37NOERROR, 162 ms, authoritativenoyes / yesrefused-
dns3.youku.com 47.241.207.17NOERROR, 174 ms, authoritativenoyes / yesrefused-
dns3.youku.com 2401:b180:4100::9NOERROR, 185 ms, authoritativenoyes / yesrefused-
dns4.youku.com 140.205.122.88NOERROR, 10 ms, authoritativenoyes / yesrefused-
dns4.youku.com 2401:b180:4100::10NOERROR, 188 ms, authoritativenoyes / yesrefused-

Checks

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: dns2.youku.com (106.11.41.145): read udp 46.225.38.91:52594->106.11.41.145:53: i/o timeout; dns2.youku.com (106.11.35.17): read udp 46.225.38.91:38672->106.11.35.17:53: i/o timeout.
    #14
  • ✓ All authoritative #15
    Every responding nameserver answers authoritatively for the zone.
  • ✓ No recursion #16
    The nameservers do not answer recursive queries for other domains.
  • ✓ No version disclosed #17
    The nameservers don't reveal their software version.
  • ✓ Zone transfers refused #18
    No nameserver allows a zone transfer to the public.
  • ✓ TCP supported #19
    All nameservers answer over TCP.
  • ✓ EDNS supported #20
    All nameservers support EDNS(0).
  • ✓ Public addresses #21
    All nameserver addresses are publicly routable.

SOA

warn

serial 2017051810 · primary dns1.youku.com

Found

Primary (MNAME)
dns1.youku.com
Contact (RNAME)
hostmaster.hichina.com
Serial
2017051810
Refresh / retry
3600 s / 1200 s
Expire
3600 s
Negative TTL
360 s

Serial per nameserver

NameserverSerial
dns1.youku.com (140.205.103.193)2017051810
dns1.youku.com (2401:b180:4100::3)2017051810
dns2.youku.com (2401:b180:4100::8)2017051810
dns3.youku.com (47.88.74.37)2017051810
dns3.youku.com (47.241.207.17)2017051810
dns3.youku.com (2401:b180:4100::9)2017051810
dns4.youku.com (140.205.122.88)2017051810
dns4.youku.com (2401:b180:4100::10)2017051810

Checks

  • ✓ Serial 2017051810 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    expire 1h is shorter than 7d; secondaries stop answering too soon when the primary is down; expire 1h must be longer than refresh + retry. Current values: refresh 1h, retry 20m, expire 1h, negative TTL 6m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.youku.com is one of the listed nameservers.
  • ✓ Contact hostmaster@hichina.com #25
    The SOA RNAME hostmaster.hichina.com means hostmaster@hichina.com.
  • ✓ Date-based serial #26
    The serial 2017051810 follows the YYYYMMDDnn convention (2017-05-18).

DNSSEC

info

Not signed

Found

Validated by resolver
no
Lookup error: read udp 46.225.38.91:56304->140.205.103.193:53: i/o timeout

Checks

  • i
    Could not be checked
    The DNSSEC lookup failed, so this could not be checked: read udp 46.225.38.91:56304->140.205.103.193:53: i/o timeout
    #27

Records

info

12 records at the apex

Found

Read from
140.205.103.193:53
TypeValueTTL
SOAdns1.youku.com. hostmaster.hichina.com. 2017051810 3600 1200 3600 360600
NSdns4.youku.com.86400
NSdns3.youku.com.86400
NSdns2.youku.com.86400
NSdns1.youku.com.86400
A106.11.43.107300
AAAA2408:4001:f00::1af300
AAAA2408:4001:f10::8300
MX5 mx1.tudou.com.300
MX5 mx2.tudou.com.300
TXT"v=spf1 include:spf1.staff.mail.aliyun.com -all"300
TXT"_globalsign-domain-verification=nK-wwYyS2ISLTC9eY6qqWjB14YPsx6cr9Uz3iTuAGV"300

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, AAAA 5m, MX 5m, NS 1d. The NS TTL at the parent is 2d and in the zone 1d; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • ✓ No wildcard #34
    Names that don't exist return NXDOMAIN.
  • i
    No CAA records
    Without CAA records any certificate authority may issue certificates for this domain. A CAA record limits issuance to the CAs you use.
    #35