dns operations s. moonesamy eland systems [email protected] afrinic 11 november 2009 1
TRANSCRIPT
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Domain Name System
AfriNIC 11 – DNS Operations
Lookup service
Globally unique public name space
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DNS Tree
AfriNIC 11 – DNS Operations
com org net cm tg sn za
afrinic.net gouv.sn
www.gouv.sn
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Domain names
AfriNIC 11 – DNS Operations
Hostname [A – Z] [0 – 9] hyphen
US ASCII
IDN
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Terminology
AfriNIC 11 – DNS Operations
DNS label
www . gouv . sn
DNS Zone
www . afrinic . netmeeting . afrinic . net
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DNS Query
AfriNIC 11 – DNS Operations
dig -t A www.afrinic.net
;; QUESTION SECTION:
;www.afrinic.net. IN A
;; ANSWER SECTION:
www.afrinic.net. 86400 IN A 196.216.2.1
;; Query time: 80 msec
;; MSG SIZE rcvd: 340
QNAME QCLASS QTYPEwww.afrinic.net IN A
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Name Servers
AfriNIC 11 – DNS Operations
dig -t ns sn
;; QUESTION SECTION:
;sn. IN NS
;; ANSWER SECTION:
sn. 67264 IN NS ns.sentoo.sn.
sn. 67264 IN NS ns-sn.ripe.net.
sn. 67264 IN NS ns1.ird.fr.
sn. 67264 IN NS ns3.nic.fr.
sn. 67264 IN NS ns.ucad.sn.
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Transport Protocols
UDP
TCP
512 octet payload
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EDNS0
Extension Mechanism for DNS allows the transport of larger DNS packets over UDP
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What could go wrong?
Root servers
misconfiguration
firewalls
Authoritative servers
Domain Name Registry
Unreachable servers
DNS Operations
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Thank you
AfriNIC 11 – DNS Operations