sengager.fr

ns1.sfrbusinessteam.fr, ns2.sfrbusinessteam.fr

Found

Parent zone

fr

Delegation from

d.nic.fr (194.0.9.1)

NS at the parent

ns1.sfrbusinessteam.fr, ns2.sfrbusinessteam.fr

NS in the zone

ns1.sfrbusinessteam.fr, ns2.sfrbusinessteam.fr

Checks

• i

  2 nameservers

  Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns1.sfrbusinessteam.fr, ns2.sfrbusinessteam.fr.

  #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 0 IPv6 /48s.
• i

  All nameservers in one AS

  All nameserver addresses are announced by one network operator (AS15557 (LDCOMNET - Societe Francaise Du Radiotelephone - SFR SA, FR): 2 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 .fr

  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
• !

  No IPv6

  None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.

  #13

2 of 2 addresses answer authoritatively

Found

Checks

• ✓ All respond #14

  All 2 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.
• !

  Software version disclosed

  These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: ns1.sfrbusinessteam.fr: "Microsoft DNS 6.1.7601 (1DB15F75)"; ns2.sfrbusinessteam.fr: "Microsoft DNS 6.1.7601 (1DB15F75)". Hide or replace the version string.

  #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.

serial 401 · primary ns1.sfrbusinessteam.fr

Found

Primary (MNAME)

ns1.sfrbusinessteam.fr

Contact (RNAME)

hostmaster.psie.local

Serial

401

Refresh / retry

900 s / 600 s

Expire

86400 s

Negative TTL

3600 s

Serial per nameserver

Checks

• ✓ Serial 401 everywhere #22

  All nameservers serve the same version of the zone.
• !

  Unusual SOA timers

  refresh 15m is outside 20m–1d; expire 1d is shorter than 7d; secondaries stop answering too soon when the primary is down. Current values: refresh 15m, retry 10m, expire 1d, negative TTL 1h.

  #23
• ✓ Primary is a public nameserver #24

  The primary nameserver ns1.sfrbusinessteam.fr is one of the listed nameservers.
• ✓ Contact hostmaster@psie.local #25

  The SOA RNAME hostmaster.psie.local means hostmaster@psie.local.
• ✓ Counter serial #26

  The serial 401 is a plain counter.

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