In this case the most important part (the highest node in the address hierarchy) is on the LEFT (192) not the RIGHT. ( 2003080800 ; serial number 3h ; refresh 15m ; update retry 3w ; expiry 3h ; nx = nxdomain ttl ) IN NS ns1. If you want to change the host names in the assigned subnet they must be notified to the authority for that Class C address. ;qualified 66 IN CNAME 66.64/27 ;unqualified name 67 IN CNAME 67.64/27 .... Unlike IPv4, where reverse mapping is frequently not delegated to the end user, IPv6 allows and encourages delegated reverse mapping.
This is a tad awkward and would make it impossible to construct a sensible tree structure that could be searched in a single lifetime. Generally, this is unacceptable since such requests may encounter indifference, cost or questions. ; definition of our target 192.1/27 subnet ; name servers for subnet reverse map 64/27 IN NS ns1. ; IPs addresses in the subnet - all need to be defined ; except 64 and 95 since they are the subnets ; network and broadcast addresses not hosts/nodes 65 IN CNAME 65.64/.192. 93 IN CNAME 93.64/27 94 IN CNAME 94.64/27 ; end of 192.1/27 subnet ..... ( 2003080800 ; serial number 3h ; refresh 15m ; update retry 3w ; expiry 3h ; nx = nxdomain ttl ) IN NS ns1. ; IPs addresses in the subnet - all need to be defined ; except 64 and 95 since they are the subnets ; network and broadcast addresses not hosts/nodes 65 IN PTR fred. The end user can therefore be responsible for creation of reverse-mapping zone files using the IP6. ARPA domain used for reverse mapping of IPv4 addresses and is shown in Figure 3.2 below. ARPA Reverse Mapping Assume the user has been allocated from a RIR (Regional Internet Registry) or an LIR(ISP/SP) a fairly typical IPv6 range: Note IPv6 block allocations, like many other issues in IPv6, are still relatively fluid but are typically /48 or /56 - exceptionally /64.
Thus, the IPv6 address splits in the table below achieve the same result. ; Start of Authority RR defining the key characteristics of the zone (domain) @ IN SOA ns1. ( 2010121500 ; sn = serial number 12h ; refresh = refresh 15m ; retry = refresh retry 3w ; expiry = expiry 2h ; nx = = nxdomain ttl ) ; name server RRs for the domain IN NS ns1. In the case of IPv6 reverse-mapping (and forward-mapping) may not be a simple process as discussed in the next section.
We defined the normal domain name structure as a tree starting from the root. This process is independent of the ISP or other authority that allocated the IP name space.
We write a normal domain name LEFT to RIGHT but the hierarchical structure is RIGHT to LEFT. If the addresses were to change then the owner of the domain that maps these addresses would be able to make the necessary changes directly with either the relevant registrar i.e. ; end of 192.1/27 subnet Now you have to change your reverse map zone names in the file to reflect the above change.
There are times however when we want to be able to find out the name of the host whose IP address = x.x.x.x (or x:x:x:x:x for IPv6).
Sometimes this is required for diagnostic purposes, more frequently these days it is used for security purposes to trace a hacker or spammer.
See: man (search for zone) Other than the missing zone statements in dhcpd.conf, I don't see anything else wrong.
A normal DNS query would be of the form 'what is the IP of host=www in domain=mydomain.com'.
However, I am at a block on getting the reverse dns updating to work.
The message that is get in the syslog is: Jun 16 rover dhcpd: Added new forward map from Bowser.to 192.168.0.10 Jun 16 rover dhcpd: unable to add reverse map from 10.0.168.192. I was waiting on getting it working first before complicating things.) I would appreciate any assistance with this problem. Now for the long part - the config files (minus the comments): ---------- ddns-update-style interim; default-lease-time 600; max-lease-time 7200; log-facility local7; subnet 192.168.0.0 netmask 255.255.255.0 ---------- ---------- include "/etc/bind/options"; zone "." ; zone "localhost" ; zone "127.in-addr.arpa" ; zone "0.in-addr.arpa" ; zone "255.in-addr.arpa" ; include "/etc/bind/local"; ---------- options ---------- options ; ---------- local ---------- acl ; zone "" IN ; zone "0.168.192." IN ; ---------- zone.0.168.192 ---------- $TTL 300 @ IN SOA rover. ( 1 ; Serial no., based on date 21600 ; Refresh after 6 hours 3600 ; Retry after 1 hour 604800 ; Expire after 7 days 3600 ; Minimum TTL of 1 hour ) 1 IN PTR rover @ IN NS rover 10 IN PTR bowser ----------- (A reverse dns lookup on bowser works (nslookup 192.168.0.10)).
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