sigmaaldrich.com

Checked 22 October 2026, 10:42 UTC · via 8.8.8.8
!Passed with warnings
25 passed 1 warning 0 failed 5 info

Registration

info

.com generic · Key-Systems GmbH · expires 2027-07-19

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
Key-Systems GmbH
Registered
20 July 1998
Last changed
17 June 2026
Expires
19 July 2027
Status
client delete prohibited, client transfer prohibited
Registry nameservers
ns01.brandshelter.com, ns02.brandshelter.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 2027-07-19 #3
    The registration is valid until 2027-07-19 (269 days).
  • ✓ Transfer locked #4
    Registry status: client delete prohibited, client transfer prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

ns01.brandshelter.com, ns02.brandshelter.net

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
ns01.brandshelter.com, ns02.brandshelter.net
NS in the zone
ns01.brandshelter.com, ns02.brandshelter.net
NameserverAddressesNetwork (AS)Glue
ns01.brandshelter.com193.227.117.15 2a04:2b00:14cc::15AS1921 RCODEZERO-ANYCAST-SEC1-TLD - ipcom GmbH, AT AS1921 RCODEZERO-ANYCAST-SEC1-TLD - ipcom GmbH, AT193.227.117.15 2a04:2b00:14cc::15
ns02.brandshelter.net194.50.187.16 2a04:2b00:14dd::16AS1921 RCODEZERO-ANYCAST-SEC1-TLD - ipcom GmbH, AT AS1921 RCODEZERO-ANYCAST-SEC1-TLD - ipcom GmbH, AT-

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns01.brandshelter.com, ns02.brandshelter.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.
  • ✓ Nameservers in different networks #10
    The nameservers are spread over 2 IPv4 /24s and 2 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS1921 (RCODEZERO-ANYCAST-SEC1-TLD - ipcom GmbH, AT): 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
  • ✓ Nameserver names under 2 TLDs #12
    Nameserver names use the TLDs .com, .net.
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

info

4 of 4 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns01.brandshelter.com 193.227.117.15NOERROR, 3 ms, authoritativenoyes / yesrefusedRcodeZero DNS
ns01.brandshelter.com 2a04:2b00:14cc::15NOERROR, 4 ms, authoritativenoyes / yesrefusedRcodeZero DNS
ns02.brandshelter.net 194.50.187.16NOERROR, 11 ms, authoritativenoyes / yesrefusedreg-wie1
ns02.brandshelter.net 2a04:2b00:14dd::16NOERROR, 12 ms, authoritativenoyes / yesrefusedreg-wie1

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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: ns01.brandshelter.com: "RcodeZero DNS"; ns02.brandshelter.net: "reg-wie1".
    #17
  • ✓ 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

pass

serial 2026101000 · primary ns01.brandshelter.com

Found

Primary (MNAME)
ns01.brandshelter.com
Contact (RNAME)
tech.brandshelter.com
Serial
2026101000
Refresh / retry
28800 s / 600 s
Expire
1209600 s
Negative TTL
300 s

Serial per nameserver

NameserverSerial
ns01.brandshelter.com (193.227.117.15)2026101000
ns01.brandshelter.com (2a04:2b00:14cc::15)2026101000
ns02.brandshelter.net (194.50.187.16)2026101000
ns02.brandshelter.net (2a04:2b00:14dd::16)2026101000

Checks

  • ✓ Serial 2026101000 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 10m, expire 14d, negative TTL 5m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns01.brandshelter.com is one of the listed nameservers.
  • ✓ Contact tech@brandshelter.com #25
    The SOA RNAME tech.brandshelter.com means tech@brandshelter.com.
  • ✓ Date-based serial #26
    The serial 2026101000 follows the YYYYMMDDnn convention (2026-10-10).

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

43 records at the apex

Found

Read from
193.227.117.15:53
TypeValueTTL
SOAns01.brandshelter.com. tech.brandshelter.com. 2026101000 28800 600 1209600 300300
NSns01.brandshelter.com.300
NSns02.brandshelter.net.300
A185.123.52.199600
AAAA2a10:ec6:1:3:185:123:52:199600
MX10 mxa-005f4802.gslb.pphosted.com.300
MX10 mxb-005f4802.gslb.pphosted.com.300
TXT"MS=ms81241719"600
TXT"_5jt6v6buzm652o0z2mpgfxv08t5f7ad"600
TXT"_cftn9x585yz9b3cb3i1ari4j6bh65sp"600
TXT"_cy951hhy8mw82q69dkjgsax6jh39est"600
TXT"_pxs3vgr0bwkirtyi8ubxg9uojc9q1d7"600
TXT"_qeapzxdelh7xfhnlqcuywo7ygi7hifv"600
TXT"_svi1ncu4cumr6nw5k1znkab0qr691rv"600
TXT"_wet0jp28oexnv3cnu099w2wr13wnkzq"600
TXT"cmbglg0tbxlzvxgtmc7mr45jc7wxl9w4"600
TXT"z88l2xkshn69czfqgmsj9c6d50vqxf7c"600
TXT"yandex-verification: fe89f4ca9b23bb00"600
TXT"_validation-contactemail webadmin-devops@merckgroup.com"600
TXT"globalsign-domain-verification=0B0F53EC216D660702AE4A9A63D72F74"600
TXT"globalsign-domain-verification=0B6BE80F6F80EB75317351E4028F99FA"600
TXT"globalsign-domain-verification=2B6B5C4C6BBB5B5AAE6F089837878D86"600
TXT"globalsign-domain-verification=3263E2B0098AC99D0EAE1857F3721EC2"600
TXT"globalsign-domain-verification=4b8078824d1dae9350e707486ba9ddcf"600
TXT"globalsign-domain-verification=7E9C6273286D016BC739F611C23B14B3"600
TXT"globalsign-domain-verification=89F2BF086C30F3085DED32FBBB0991A3"600
TXT"globalsign-domain-verification=9312CD11FDE849F8FCAA78D6BCF99770"600
TXT"globalsign-domain-verification=B950605920163BED51E14CB3C71113BB"600
TXT"globalsign-domain-verification=BD227E1F68FD41038F4DAD17EF9A42BB"600
TXT"globalsign-domain-verification=D947A57FF568DBB84DFA710946DACB6A"600
TXT"globalsign-domain-verification=FA2F4FC98028B53BED16786E870D92E7"600
TXT"globalsign-domain-verification=c000b885bf4ac44d3c1ae3a95c241dde"600
TXT"globalsign-domain-verification=dface27f0430d7d08dfadc50dae06cbe"600
TXT"globalsign-domain-verification=f18a5fb3e440e14833097a09ffff7640"600
TXT"google-site-verification=KKFNroCgQrT3ZAFS7xbHZcXZsBhazWIB3vtKfOb6ouM"600
TXT"google-site-verification=O9x5KvwEgll7z5DhE7KwBzaHYHIwh2LjiLwfWZdO5kE"600
TXT"google-site-verification=ZC0ucf6BRwGfNGBgaSbxM5KdOZnUrckPsTDLMlRoLMs"600
TXT"google-site-verification=fOh8OkUz9z2sxgSRHJAX7-q6I5C-HiR3mcm3yj9uU0E"600
TXT"_globalsign-domain-verification=49OWFydCiWRZ_S8Vdp-VLIQnUn-kkSxNGgyJMa_138"600
TXT"_globalsign-domain-verification=6bP9qCGkjtv6lK1oUUk1GW_aLlwQ_rTa1zcOrqYRVM"600
TXT"_globalsign-domain-verification=i-eF5zY4dQy_1FzurxY-vB_ehho_ANc_RUBJNFcEiB"600
TXT"_globalsign-domain-verification=y-WbZfGH3iscpkgt-BmoaO4oBPfJ1RVC-VsPFSFLIe"600
TXT"v=spf1 include:spf-005f4802.pphosted.com include:spf.protection.outlook.com include:_spf.esi-sa.com ~all"600

Checks

  • ✓ TTLs within range #32
    TTLs: A 10m, AAAA 10m, MX 5m, NS 5m. The NS TTL at the parent is 2d and in the zone 5m; 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