MySQL replication status monitoring

Anurag Bhatia
Background I am running my own authoritative DNS servers for the last few years. In earlier stages I just used registrar-provided DNS, later moved to “Cloud provider” provided DNS and ultimately settled for running my own auth DNS. Two major requirements pushed me to self-host auth DNS: Requirement of REST API for DNS needed by the web servers to resolve Letsencrypt certbot DNS-based challenge. This allows me to have internally hosted tools with Letsencrypt issues TLS certificates instead of self-signed ones.

Using bgpq3 for automated filter generation

Anurag Bhatia
Came across excellent tool called “bgpq3” from one of recent posts in NANOG mailing list. This tool can general filters for a given ASN for Cisco or Juniper based on RADB’s data. E.g Juniper style config for AS54456 (1st ASN on which I worked on!) :) anurag@server7 ~> bgpq3 -Jl Cloudaccess as54456 policy-options { replace: prefix-list Cloudaccess {;;;; } } anurag@server7 ~> Cisco style config: > anurag@server7:~$ bgpq3 -l Cloudaccess as54456 no ip prefix-list Cloudaccess ip prefix-list Cloudaccess permit 199.

Simple bash script for IP-ASN mapping

Anurag Bhatia
Whenever I see a new unknown IP range, it gets hard to find exact source of that IP within command shell. Recently, I found a very interesting source of that information from Team Cymru. Here’s the resource. I figured out (with a friend’s help) that using their whois server - one can actually grab limited information as required. E.g anurag@laptop:~$ whois -h " -v" AS | IP | BGP Prefix | CC | Registry | Allocated | AS Name 15169 | 8.