Chapter 10: Network Naming Flashcards
How long can Domain names be?
up to 255 characters including periods.
Where is the hosts file stored in windows?
\Windows\System32\Drivers\Etc
What are DNS root servers?
called “.” or “dot”
-13 powerful DNS servers.
What are top-level domain servers?
- just below DNS root in the hierarchy
- delegate to thousands of second-level DNS servers
What are second-level DNS servers?
-support individual computers.
What were the original top-level domain servers?
-com, org, net, edu, gov, mil, and int
What is a FQDN?
Fully qualified domain name
- complete DNS name
- root on far right, names of the domains in order to left of the root. Host name far left.
- “.com” “.net” needed for computers visible on internet
- not required on a private TCP/IP network
What is a DNS server?
A server running DNS server software
What is a zone?
A containter for a single domain that gets filled with records.
What is a record?
line in the zone data that maps a FQDN to an ip address
What is an authoritative DNS server?
- lists all host names on the domain and corresponding IP addresses
- also called Start of Authority(SOA)
what is a name server?
-subordinate to authoritative DNS server
Where is the DNS info kept in Linux?
/etc/resolv.conf
- where to edit DNS info
- also a graphical editor
How do you display a cache of recently resolved FQDNs?
ipconfig /displaydns
Describe two types of DNS servers.
- Windows Server 2008: DNS is built in
- Unix/linux systems you can use BIND
What is a forward lookup zone?
- ip adddresses and FQDNs for computers in a domain
- requires a SOA
- was at least one SOA and one NS record
- usually have some A record
What is a cname?
Canonical name
-acts like an alias
What is a MX record?
-used by SMTP servers to determine where to send mail
what is a reverse lookup zone?
- enables system to determine a FQDN by knowing the ip address.
- pointer records
What is an active directory integrated zone?
- NetBT: Netbios over TCP/IP
- CIFS: Common Internet File System
- originally called Server Message Block (SMB)
- Samba: for Unix/Linux makes non-windows systems act like windows.
- organizes computers into groups.
What is a workgroup?
-name that organizes groups of computers.
Describe a windows domain.
- All computers within domain authenticate to a domain controller.
- group of computers controlled by computer running windows server.
Describe active directory.
- Super domain.
- Organization of related computers that shares one or more windows domains.
- no single domain controller.
Describe Common Internet File System.
- can’t add records to secondary servers.
- active directory integrated zone all domain servers (DNS servers) are equal.
Describe DDNS.
Dynamic DNS.
-DNS servers get automatic updates of IP addresses of computers in their forward lookup zones, by talking to local DHCP server.
What command forces DNS server to update its records?
ipconfig /registerdns
Describe DNSSEC.
DNS security
-authentication and authorization specification to prevent bad guys from impersonating DNS servers.
what is a dynamic DNS server?
- www.tzo.com
- maps home or office router to a domain name.
What command eliminates DNS caches on the local system?
ipconfig /flushdns
-must remember that web browsers also have caches.
what command gives the ip address and name of default DNS server?
nslookup
Describe DIG.
Domain information groper
-similar to nslookup, runs noninteractively
Describe WINS.
- NetBIOS names still appear in older versions of windows
- LMHOSTS: text file to reduce overhead from NetBios Broadcasts.
How do you troubleshoot WINS.
nbstat: helps deal with net bios problems
nbstat -c : check current netbious name cache.
How do you troubleshoot TCP/IP networks?
- diagnose the NIC
- Diagnose locally
- Check IP address and subnet mask
- Netstat: all current connections to system.
- netstat -s: shows statistics to diagnose a problem
- Diagnose gateway: ping router, try local and internet
- Diagnose to internet: tracert.
