Does anyone out there have any experience with a script, tool or appliance that would help manage the creation and maintenance of DNS records for Layer 3 interfaces on routers and switches?
We'd like to move toward this practice to help with troubleshooting and IPAM, but it's not feasible to do it manually. At a minimum, I was mulling over the idea of writing a script that would poll a device via SNMP to obtain interface information, parse it, compare the results to DNS, then generate a report if it found a miss. It wouldn't be fully-automated, but it would be better than doing that portion of the work manually. Cleaning up dead entries would be another issue.
Pedersen, Sean (Sean.Pedersen) writes:
Does anyone out there have any experience with a script, tool or appliance that would help manage the creation and maintenance of DNS records for Layer 3 interfaces on routers and switches?
Hi Sean,
Part of Netdot's (Network Documentation Tool - netdot.uoregon.edu)
functionality is to produce automated DNS zone exports based on the
IPAM information it manages, including L3 devices and their interfaces.
We'd like to move toward this practice to help with troubleshooting and IPAM, but it's not feasible to do it manually. At a minimum, I was mulling over the idea of writing a script that would poll a device via SNMP to obtain interface information, parse it, compare the results to DNS, then generate a report if it found a miss. It wouldn't be fully-automated, but it would be better than doing that portion of the work manually. Cleaning up dead entries would be another issue.
Writing the scripts isn't too difficult, but as you write, you still
need to detect dead entries, differentiate between an interface
disappearing because it was deprovisioned, and the sudden disappearance
of a large number of IFs due to a script failing (is 1 dead entry
acceptable ? 10 ? 1000 ?)
Cheers,
Phil
We use a customized version of this:
https://gist.github.com/778830
http://cluepon.net/ras/generate_dnsptr_generic_php
A relatively simple example using php, with the net-snmp module and Net_IPv4
from PEAR. For extra bonus points, it parses your BGP state and uses any
neighbor ASNs it finds for the remote side of your /30 or /31s, and it
resolves point-to-point SVIs to physical ports by checking against the vlan
tables. The later part was only tested on Cisco 6500s, and I haven't touched
that code (or those boxes) in many many years, so no guarantees about using
it on anything else. 
Out of date DNS PTRs in traceroute make baby jesus cry, so please use
copiously.
Thanks to everyone that responded. Based on the information from this list and several other areas I posted the same question, it seems like a feasible goal.
If anyone has any ideas on how to either reduce my sleeping requirements or extend the number of hours in a day so that I can actually implement this, I would love to hear from you. 
Does anyone out there have any experience with a script, tool or appliance that would help manage the creation and maintenance of DNS records for Layer 3 interfaces on routers and switches?
http://www.nanog.org/meetings/nanog26/presentations/stephen.pdf
ftp://ftp.isc.org/isc/toolmakers/
We'd like to move toward this practice to help with troubleshooting and IPAM, but it's not feasible to do it manually. At a minimum, I was mulling over the idea of writing a script that would poll a device via SNMP to obtain interface information, parse it, compare the results to DNS, then generate a report if it found a miss. It wouldn't be fully-automated, but it would be better than doing that portion of the work manually. Cleaning up dead entries would be another issue.
AS6461 once had the bulk of its reverse DNS auto-generated from awk scripts. It's the only way to travel.
Joe