Domain report: slack.com

Registration

info

.com generic · MarkMonitor Inc. · expires 2027-10-20

Found

TLD: .com (generic)
ICANN policies apply: yes
Registrar: MarkMonitor Inc.
Registered: 21 October 1992
Last changed: 18 September 2025
Expires: 20 October 2027
Status: client delete prohibited, client transfer prohibited, client update prohibited, server delete prohibited, server transfer prohibited, server update prohibited
Registry nameservers: ns-1493.awsdns-58.org, ns-166.awsdns-20.com, ns-1901.awsdns-45.co.uk, ns-606.awsdns-11.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 2027-10-20 #3

The registration is valid until 2027-10-20 (362 days).
✓ Transfer locked #4

Registry status: client delete prohibited, client transfer prohibited, client update prohibited, server delete prohibited, server transfer prohibited, server update prohibited.
✓ Registry and delegation match #5

The nameservers registered at the registry are the ones published in DNS.

Delegation

info

ns-1493.awsdns-58.org, ns-166.awsdns-20.com, ns-1901.awsdns-45.co.uk, ns-606.awsdns-11.net

Found

Parent zone: com
Delegation from: a.gtld-servers.net (192.5.6.30)
NS at the parent: ns-1493.awsdns-58.org, ns-166.awsdns-20.com, ns-1901.awsdns-45.co.uk, ns-606.awsdns-11.net
NS in the zone: ns-1493.awsdns-58.org, ns-166.awsdns-20.com, ns-1901.awsdns-45.co.uk, ns-606.awsdns-11.net

Nameserver	Addresses	Network (AS)	Glue
ns-1493.awsdns-58.org	205.251.197.213 2600:9000:5305:d500::1	AS16509 AMAZON-02 - Amazon.com, Inc., US AS16509 AMAZON-02 - Amazon.com, Inc., US	-
ns-166.awsdns-20.com	205.251.192.166 2600:9000:5300:a600::1	AS16509 AMAZON-02 - Amazon.com, Inc., US AS16509 AMAZON-02 - Amazon.com, Inc., US	205.251.192.166 2600:9000:5300:a600::1
ns-1901.awsdns-45.co.uk	205.251.199.109 2600:9000:5307:6d00::1	AS16509 AMAZON-02 - Amazon.com, Inc., US AS16509 AMAZON-02 - Amazon.com, Inc., US	-
ns-606.awsdns-11.net	205.251.194.94 2600:9000:5302:5e00::1	AS16509 AMAZON-02 - Amazon.com, Inc., US AS16509 AMAZON-02 - Amazon.com, Inc., US	-

Checks

✓ 4 nameservers #6

Delegated to ns-1493.awsdns-58.org, ns-166.awsdns-20.com, ns-1901.awsdns-45.co.uk, ns-606.awsdns-11.net.
✓ 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 4 IPv4 /24s and 4 IPv6 /48s.
i

All nameservers in one AS

All nameserver addresses are announced by one network operator (AS16509 (AMAZON-02 - Amazon.com, Inc., US): 8 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 4 TLDs #12

Nameserver names use the TLDs .com, .net, .org, .uk.
✓ All reachable over IPv6 #13

Every nameserver has an IPv6 address.

Nameservers

pass

8 of 8 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns-1493.awsdns-58.org 205.251.197.213	NOERROR, 3 ms, authoritative	no	yes / yes	refused	-
ns-1493.awsdns-58.org 2600:9000:5305:d500::1	NOERROR, 4 ms, authoritative	no	yes / yes	refused	-
ns-166.awsdns-20.com 205.251.192.166	NOERROR, 9 ms, authoritative	no	yes / yes	refused	-
ns-166.awsdns-20.com 2600:9000:5300:a600::1	NOERROR, 9 ms, authoritative	no	yes / yes	refused	-
ns-1901.awsdns-45.co.uk 205.251.199.109	NOERROR, 9 ms, authoritative	no	yes / yes	refused	-
ns-1901.awsdns-45.co.uk 2600:9000:5307:6d00::1	NOERROR, 9 ms, authoritative	no	yes / yes	refused	-
ns-606.awsdns-11.net 205.251.194.94	NOERROR, 4 ms, authoritative	no	yes / yes	refused	-
ns-606.awsdns-11.net 2600:9000:5302:5e00::1	NOERROR, 4 ms, authoritative	no	yes / yes	refused	-

Checks

✓ All respond #14

All 8 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.
✓ 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 1 · primary ns-1493.awsdns-58.org

Found

Primary (MNAME): ns-1493.awsdns-58.org
Contact (RNAME): awsdns-hostmaster.amazon.com
Serial: 1
Refresh / retry: 7200 s / 900 s
Expire: 1209600 s
Negative TTL: 300 s

Serial per nameserver

Nameserver	Serial
ns-1493.awsdns-58.org (205.251.197.213)	1
ns-1493.awsdns-58.org (2600:9000:5305:d500::1)	1
ns-166.awsdns-20.com (205.251.192.166)	1
ns-166.awsdns-20.com (2600:9000:5300:a600::1)	1
ns-1901.awsdns-45.co.uk (205.251.199.109)	1
ns-1901.awsdns-45.co.uk (2600:9000:5307:6d00::1)	1
ns-606.awsdns-11.net (205.251.194.94)	1
ns-606.awsdns-11.net (2600:9000:5302:5e00::1)	1

Checks

✓ Serial 1 everywhere #22

All nameservers serve the same version of the zone.
✓ Timers within recommendations #23

SOA refresh 2h, retry 15m, expire 14d, negative TTL 5m.
✓ Primary is a public nameserver #24

The primary nameserver ns-1493.awsdns-58.org is one of the listed nameservers.
✓ Contact awsdns-hostmaster@amazon.com #25

The SOA RNAME awsdns-hostmaster.amazon.com means awsdns-hostmaster@amazon.com.
✓ Counter serial #26

The serial 1 is a plain counter.

DNSSEC

pass

Signed, DS published at parent

Found

Validated by resolver: yes
Signatures valid until: 22 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
296	ECDSAP256SHA256 (13)	SHA256 601D7EC07E7DEE6E…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
5952	ZSK (256)	ECDSAP256SHA256 (13)
23756	ZSK (256)	ECDSAP256SHA256 (13)
296	KSK (257)	ECDSAP256SHA256 (13)

Checks

✓ Signed and validated #27

The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
✓ DS matches a key #28

The DS record at the parent matches a key in the zone: key tag 296 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Short-lived signatures (online signing) #30

Signatures are valid for 2h0m0s and created on demand; the current one was made at 2026-10-22 09:44 UTC and expires at 2026-10-22 11:59 UTC.

Records

warn

31 records at the apex

Found

Read from: 205.251.197.213:53

Type	Value	TTL
SOA	ns-1493.awsdns-58.org. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 300	900
NS	ns-1493.awsdns-58.org.	3600
NS	ns-166.awsdns-20.com.	3600
NS	ns-1901.awsdns-45.co.uk.	3600
NS	ns-606.awsdns-11.net.	3600
A	18.159.197.225	60
A	3.68.124.168	60
A	52.29.238.212	60
A	3.68.175.98	60
A	3.68.170.153	60
A	3.68.124.95	60
MX	1 aspmx.l.google.com.	60
MX	10 aspmx2.googlemail.com.	60
MX	10 aspmx3.googlemail.com.	60
MX	5 alt1.aspmx.l.google.com.	60
MX	5 alt2.aspmx.l.google.com.	60
TXT	"OSSRH-54733"	3600
TXT	"_0vidyxobp6x350odqhb4fo7fdxhmtq3"	3600
TXT	"google-site-verification=2PK67oVPNyEtS1avSlr3PhH5nSiFuticbQv_bT4pM2k"	3600
TXT	"google-site-verification=KqX3Ngw0XEjz_0GVx_xwFFlCoO-bskhqU_lxv0Q77mk"	3600
TXT	"google-site-verification=QvelFPjIOe3Vavw0q-aAVYaAPKmWCRjmmVVEAjgfjQc"	3600
TXT	"google-site-verification=efuXt5-oMr2CdNmVi6A9IO29KMKifpseD1qokxjWwcE"	3600
TXT	"google-site-verification=kB1KvgpSk9YkHsFmsj1VPI5YmDvfKctPxnplhGjyqtE"	3600
TXT	"google-site-verification=o2grd1TLmZZ8GrqbhVIFtzO2MRLTtSUpBBIBYfhQVCQ"	3600
TXT	"google-site-verification=v-LLB__IhraaI7ZzuE3jvRFIm2vERPLzWoepAEZJtKQ"	3600
TXT	"hubspot-developer-verification=OTE4NzYxYTgtMDUwZi00MzgzLTk2YTUtZDAwNjBlODg1MWM0"	3600
TXT	"spycloud-domain-verification=02e4c0be-cf43-44e4-beaf-4f99702ca632"	3600
TXT	"v=spf1 include:_spf.qualtrics.com include:mail.zendesk.com include:_spfextra.slack.com -all"	3600
CAA	0 iodef "mailto:hostmaster@slack-corp.com"	300
CAA	0 issue "digicert.com; account=455b15ed272bed097725c6ea50e89921fc57379c5338a29305c05771df65fff1"	300
CAA	0 issue "letsencrypt.org; accounturi=https://acme-v02.api.letsencrypt.org/acme/acct/1532134906"	300

Checks

!

Very low TTLs

These records have a TTL below 5m, causing extra queries and slower lookups: A (1m), MX (1m). Low TTLs are useful just before a planned change. The NS TTL at the parent is 2d and in the zone 1h; resolvers may use either.

#32
✓ No CNAME at the apex #33

The zone apex has no CNAME record.
i

Wildcard record

A random name under the zone resolves, so there is a wildcard (*) record. Typos and non-existent hosts resolve too, which can confuse mail and certificate checks.

#34
✓ CAA restricts issuance #35

Certificates may be issued by: digicert.com, letsencrypt.org.