North American Network Operators Group|
Date Prev | Date Next |
Date Index |
Thread Index |
Author Index |
Re: DNS DOS increasing?
- From: Miquel van Smoorenburg
- Date: Mon Jan 21 12:59:57 2002
- Distribution: cistron
- Newsgroups: lists.nanog
In article <cistron.171DAAD54475984F8F41345A0945DF9C39ED49@hqexchange.presidio.com>,
James Smith <jsmith@PRESIDIO.com> wrote:
> Get ready for more DOS-like behavior as systems get deployed that have 10
>second TTLs in the DNS. These systems are used to provide multi-isp
>redundancy by pinging each upstreams router, and when a ping fails, start
>giving out a dns response using the other ISP IP range. Same FQDN, new IP.
So what we need is a tunable on the caching DNS server that says
min_allowed_ttl = 300;
if (ttl < min_allowed_ttl) ttl = min_allowed_ttl;
If the above becomes a problem, this will happen.