xilinx.com

Checked 22 October 2026, 11:35 UTC · via 8.8.8.8
✗Problems found
23 passed 1 warning 1 failed 6 info

Registration

info

.com generic · MarkMonitor Inc. · expires 2028-06-18

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
MarkMonitor Inc.
Registered
19 June 1991
Last changed
17 May 2026
Expires
18 June 2028
Status
client delete prohibited, client transfer prohibited, client update prohibited
Registry nameservers
dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net
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 2028-06-18 #3
    The registration is valid until 2028-06-18 (604 days).
  • ✓ Transfer locked #4
    Registry status: client delete prohibited, client transfer prohibited, client update prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net
NS in the zone
dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net
NameserverAddressesNetwork (AS)Glue
dbru.br.ns.els-gms.att.net68.94.156.134 2001:1890:1ff:9f0:68:94:156:134AS7018 ATT-INTERNET4 - AT&T Enterprises, LLC, US AS7018 ATT-INTERNET4 - AT&T Enterprises, LLC, US-
dmtu.mt.ns.els-gms.att.net99.99.99.134 2001:1890:1ff:9f1:99:99:99:134AS7018 ATT-INTERNET4 - AT&T Enterprises, LLC, US AS7018 ATT-INTERNET4 - AT&T Enterprises, LLC, US-

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net.
    #6
  • ✓ 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 2001:1890:1ff::/48, while the other address family is spread over several networks.
    #10
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS7018 (ATT-INTERNET4 - AT&T Enterprises, LLC, US): 4 addresses). An outage or attack on that network affects all nameservers; large anycast providers mitigate this, but a secondary DNS provider adds independence.
    #11
  • i
    All nameserver names under .net
    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

4 of 4 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dbru.br.ns.els-gms.att.net 68.94.156.134NOERROR, 144 ms, authoritativenoyes / yesrefused-
dbru.br.ns.els-gms.att.net 2001:1890:1ff:9f0:68:94:156:134NOERROR, 124 ms, authoritativenono / yesrefused-
dmtu.mt.ns.els-gms.att.net 99.99.99.134NOERROR, 132 ms, authoritativenoyes / yesrefused-
dmtu.mt.ns.els-gms.att.net 2001:1890:1ff:9f1:99:99:99:134NOERROR, 111 ms, authoritativenono / yesrefused-

Checks

  • ✓ All respond #14
    All 4 nameserver addresses answered.
  • ✓ 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.
  • ✗
    No DNS over TCP
    DNS over TCP is required (RFC 7766); without it, large answers such as DNSSEC responses fail. Not answering over TCP: dbru.br.ns.els-gms.att.net (2001:1890:1ff:9f0:68:94:156:134): read tcp [2a01:4f8:1c1c:eebf::1]:50632->[2001:1890:1ff:9f0:68:94:156:134]:53: read: connection reset by peer; dmtu.mt.ns.els-gms.att.net (2001:1890:1ff:9f1:99:99:99:134): read tcp [2a01:4f8:1c1c:eebf::1]:40082->[2001:1890:1ff:9f1:99:99:99:134]:53: read: connection reset by peer.
    #19
  • ✓ EDNS supported #20
    All nameservers support EDNS(0).
  • ✓ Public addresses #21
    All nameserver addresses are publicly routable.

SOA

pass

serial 699 · primary dbru.br.ns.els-gms.att.net

Found

Primary (MNAME)
dbru.br.ns.els-gms.att.net
Contact (RNAME)
hostmaster.xilinx.com
Serial
699
Refresh / retry
86400 s / 3600 s
Expire
864000 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
dbru.br.ns.els-gms.att.net (68.94.156.134)699
dbru.br.ns.els-gms.att.net (2001:1890:1ff:9f0:68:94:156:134)699
dmtu.mt.ns.els-gms.att.net (99.99.99.134)699
dmtu.mt.ns.els-gms.att.net (2001:1890:1ff:9f1:99:99:99:134)699

Checks

  • ✓ Serial 699 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1d, retry 1h, expire 10d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dbru.br.ns.els-gms.att.net is one of the listed nameservers.
  • ✓ Contact hostmaster@xilinx.com #25
    The SOA RNAME hostmaster.xilinx.com means hostmaster@xilinx.com.
  • ✓ Counter serial #26
    The serial 699 is a plain counter.

DNSSEC

warn

Not signed

Found

Validated by resolver
no

Checks

  • !
    Not signed
    The zone is not signed with DNSSEC, so answers can be spoofed. Enable DNSSEC at your DNS provider and publish the DS record at your registrar.
    #27

Records

info

18 records at the apex

Found

Read from
68.94.156.134:53
TypeValueTTL
SOAdbru.br.ns.els-gms.att.net. hostmaster.xilinx.com. 699 86400 3600 864000 8640086400
NSdbru.br.ns.els-gms.att.net.86400
NSdmtu.mt.ns.els-gms.att.net.86400
MX10 xilinx-com.mail.protection.outlook.com.300
TXT"XSnFNOKHwPVWPnKmij8giLr16kPC1V79nLu2c2aH4xoz/bGiX2jyjMf0w5H1HI297SDkU8LzUZcAlnqyH2WhXw=="3600
TXT"atlassian-domain-verification=+ySJHRcnw4ikAdQlqcSMwmNSFBrFIXVbfjXmrj9KqWcD0WrUfcip6aO9W9IQDDm/"3600
TXT"facebook-domain-verification=mkkomgnez2i4o14jhi7524axy3n23u"3600
TXT"cisco-ci-domain-verification=1df6771bb737dca7014d43c3c6ea88ca41bf39998bb0f9d4f7d8874ab4e5efb"3600
TXT"google-site-verification=NvOcd5C5E-P7H5lzHsgkV6Qefph4XNf-QfTDO8t7aB4"3600
TXT"apple-domain-verification=NviJRcP1seWJZXbb"3600
TXT"OSSRH-75269"3600
TXT"v=spf1 include:spf.protection.outlook.com include:amazonses.com include:smtpspf.xilinx.com include:oktaspf.xilinx.com include:_spf.salesforce.com -all"3600
TXT"cisco-ci-domain-verification=2dc93a259b8777bb365115904ef9642ef3bc4e624205d9eaf41d95b73d5b03f"3600
TXT"dropbox-domain-verification=x6d2a1tedbz9"3600
TXT"ibmid=8938274b-09d1-49b5-9ec8-7cf53b342b43"3600
TXT"atlassian-domain-verification=HFlyqfcckJdaD3hZCHNeaGmdLDR505F4dtpvaqkADmWTe8Lw2cXOv7FaaT8zXJ6Z"3600
TXT"atlassian-domain-verification=CUBl/RsDOQfWaVFffiiVaCaiWbaw/SBOU3ThUJ/TZYQub06KGiaTPT9se5Yeu3uH"3600
TXT"MS=ms29172253"3600

Checks

  • ✓ TTLs within range #32
    TTLs: 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