DNS Lookup

Outil de requetes DNS (simulation locale).

Note : Cet outil fonctionne 100% cote client. Pour des requetes DNS reelles, utilisez les commandes CLI ci-dessous ou un service comme dns.google.

Reference DNS rapide

Type	Description	Exemple
A	Adresse IPv4	93.184.216.34
AAAA	Adresse IPv6	2606:2800:220:1:248:1893:25c8:1946
CNAME	Alias vers un autre nom	www.example.com → example.com
MX	Serveur mail	10 mail.example.com
TXT	Texte (SPF, DKIM, verification)	v=spf1 include:...
NS	Serveurs de noms	ns1.example.com
SOA	Start of Authority	ns1.example.com admin.example.com
PTR	Reverse DNS	host.example.com
SRV	Service (LDAP, SIP, etc.)	_ldap._tcp.example.com
CAA	Certification Authority Authorization	0 issue "letsencrypt.org"

Serveurs DNS publics

Fournisseur	IPv4 Principal	IPv4 Secondaire	IPv6
Google	8.8.8.8	8.8.4.4	2001:4860:4860::8888
Cloudflare	1.1.1.1	1.0.0.1	2606:4700:4700::1111
Quad9	9.9.9.9	149.112.112.112	2620:fe::fe
OpenDNS	208.67.222.222	208.67.220.220	2620:119:35::35
Cloudflare (Malware)	1.1.1.2	1.0.0.2	2606:4700:4700::1112
Cloudflare (Family)	1.1.1.3	1.0.0.3	2606:4700:4700::1113

Commandes DNS

dig (Linux/macOS)

# Requete A
dig example.com

# Type specifique
dig example.com MX
dig example.com TXT
dig example.com AAAA
dig example.com NS

# Serveur DNS specifique
dig @8.8.8.8 example.com

# Reponse courte
dig +short example.com

# Trace complete
dig +trace example.com

# Reverse DNS
dig -x 93.184.216.34

# Tous les types
dig example.com ANY

# Format JSON
dig +json example.com | jq

nslookup (Windows/Linux)

# Requete simple
nslookup example.com

# Type specifique
nslookup -type=MX example.com
nslookup -type=TXT example.com

# Serveur DNS specifique
nslookup example.com 8.8.8.8

# Mode interactif
nslookup
> set type=MX
> example.com

host (Linux)

# Requete simple
host example.com

# Type specifique
host -t MX example.com
host -t TXT example.com

# Reverse DNS
host 93.184.216.34

# Verbose
host -v example.com

PowerShell

# Resolve-DnsName
Resolve-DnsName example.com

# Type specifique
Resolve-DnsName example.com -Type MX
Resolve-DnsName example.com -Type TXT

# Serveur specifique
Resolve-DnsName example.com -Server 8.8.8.8

Records speciaux

SPF (Sender Policy Framework)

v=spf1 ip4:192.168.1.0/24 include:_spf.google.com -all

Mecanisme	Description
`ip4:`	Adresse IPv4 autorisee
`ip6:`	Adresse IPv6 autorisee
`include:`	Inclure la politique d'un domaine
`a`	Adresse A du domaine
`mx`	Serveurs MX du domaine
`all`	Tous les autres

Qualificateur	Signification
`+`	Pass (defaut)
`-`	Fail (rejeter)
`~`	SoftFail (marquer)
`?`	Neutral

DKIM (DomainKeys Identified Mail)

v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBA...

DMARC (Domain-based Message Authentication)

v=DMARC1; p=reject; rua=mailto:dmarc@example.com; pct=100

Tag	Description
`p=`	Politique (none, quarantine, reject)
`rua=`	Adresse pour rapports agreges
`ruf=`	Adresse pour rapports forensiques
`pct=`	Pourcentage a appliquer