Tired Topics
From NANOG
There are some topics that have been discussed on the NANOG over and over to the point that it is a dead horse, a tired or even exhausted topic. Sometimes it is because the answer is clear, sometimes it is because there are clear sides to the issue and folks are entrenched. Either way, it doesn't add anything to the list to dig thee ruts deeper.
Previously Answered Questions
Check to make sure your question hasn't already been answered before posting to the list. We recommend that you:
- Search for the relevant terms at Google;
- Search the NANOG Archives for previous answers
What is a "Tier 1" provider?
In general, there's no point to this discussion as there are too many opinions on what constitutes a "Tier 1 network". There simply is no accepted technical definition. For those who define "Tier 1" based upon economic relationships between providers, it is widley believed that the providers below do not purchase any transit:
| Level(3) Communications | AS 3356 |
| Sprint | AS 1239 |
| Verizon Business | AS 701 |
| ATT | AS 7018 |
| NTT America | AS 2914 |
| Global Crossing | AS 3549 |
| Qwest | AS 209 |
| Savvis | AS 3561 |
| TeliaNet Global Network | AS 1299 |
Are we running out of IPv4 address space?
Not today. There are projections of space exhaustion from 2009 to 2013 at the moment, but things seem to change rapidly. Space exhaustion means that allocations from IANA to RIR's, then RIR's to ISP's and end-users will no longer be available for IPv4 users. Geoff Huston's IPv4 Address Report discusses this at great length. There are methods to get around this, including NAT (and IPv6).
Why do people use RFC 1918 in customer configs?
Some organizations use RFC 1918-defined IP addresses as links in their point-to-point networks. This breaks mechanisms like Path MTU discovery and can make traceroutes look funny.
If you don't mind the breakage, go ahead and use private addresses. Just don't think that private addressing is a substitute for other security measures. One summary regarding the use of RFC 1918 addresses with respect to security is here.
NAT
We should all use NAT to save address space! or NAT is evil, everyone migrate to IPv6, quick! or NAT sure makes a great firewall!
NAT stands for Network Address Translation, which enables private IP internetworks that use nonregistered IP addresses to connect to the Internet. The pros and cons of NAT have been discussed at great length on NANOG at various times over the years, and pretty much every argument for every viewpoint has already been made. To educate yourself on the various arguments, check the NANOG archives; to learn about NAT, see RFC 3022, Traditional NAT, and RFC 2775, Internet Transparency.
How can I stop <some RBL> from blocking my server?
RBLs (Realtime Blackhole Lists) are used by some mail server operators to deny mail from particular remote mail transfer agents (MTAs) in the interests of cutting down the amount of spam their users have to handle. There are lots of RBLs, and most of them have different policies relating to what addresses appear on their lists. Some are commercial, and some are not. None of them are universally loved. History shows that discussions of RBLs on NANOG are unlikely to yield useful operational content.
My ethernet's showing a lot of packet loss/packet corruption -- any suggestions?
Before asking questions about packet loss between ethernet-connected devices, turn off auto-netogiation everywhere and configure both ends of every piece of cable to have the same speed, and the same duplex setting. No auto-negotiation. If you don't need to do that because you know it's already set up that way, check that it is indeed set up that way because you could be mistaken, or someone else could have changed it.
If, once you have done that, you are still getting problems and you're profoundly convinced that the problem is not vendor-specific -- if you're sure, in fact, that it relates to some wide-reaching, never-before-seen technical issue which will no doubt affect everybody in the world who uses ethernet -- then please feel free to send your findings to the NANOG list.
Is there any way to add zone(s) to our local DNS without having to restart specific DNS server?
This is off-topic for NANOG, which is mainly concerned with the root name server network and its operation, and registry updates of the IN-ADDR.ARPA domain. A suitable operational DNS discussion might be about why non-root name servers improperly updated overnight, a notification that such an event occurred, a technical discussion of workarounds, ETTR, or other related issues. A topic or post that would not be suitable for the NANOG discussion list would be something like "My name server is broken. Why?".
Remember, NANOG doesn't particularly want to talk about your local DNS - we're concerned with operational aspects of DNS that are mainly root-server related i.e. failed loads, breakdowns, query latency, and other problems.
For help with whatever you are using, refer to the authors of that product, and of course, Google is your friend.
How can I find out who's taken a network certification test and what's on it?
Go to Amazon.COM or your local Border's and look for books related to these tests. They are plentiful. As far as finding out who has taken the test, go to the website of the certifying organization and see if it's possible to find out there. You can't find out via NANOG, we don't track or certify people.
I'm having a problem with my broadband access or hosting.
NANOG is not for end users. See Help for End Users in the wiki.
