Bitcoin-seeder is a crawler for the Bitcoin Cash network, which exposes a list of reliable nodes via a built-in DNS server. It is derived from Pieter Wuille's bitcoin-seeder, modified for use on the Bitcoin Cash network.
- regularly revisits known nodes to check their availability
- bans nodes after enough failures, or bad behaviour
- uses the Cash Magic when establishing connections.
- keeps statistics over (exponential) windows of 2 hours, 8 hours, 1 day and 1 week, to base decisions on.
- very low memory (a few tens of megabytes) and cpu requirements.
- crawlers run in parallel (by default 24 threads simultaneously).
$ sudo apt-get install build-essential libboost-all-dev libssl-dev
Assuming you want to run a dns seed on dnsseed.example.com, you will need an authoritative NS record in example.com's domain record, pointing to for example vps.example.com:
$ dig -t NS dnsseed.example.com
;; ANSWER SECTION dnsseed.example.com. 86400 IN NS vps.example.com.
On the system vps.example.com, you can now run dnsseed:
./bitcoin-seeder -host=dnsseed.example.com -ns=vps.example.com
If you want the DNS server to report SOA records, please provide an e-mail address (with the @ part replaced by .) using -mbox.
RUNNING AS NON-ROOT
Typically, you'll need root privileges to listen to port 53 (name service).
One solution is using an iptables rule (Linux only) to redirect it to a non-privileged port:
$ iptables -t nat -A PREROUTING -p udp --dport 53 -j REDIRECT --to-port 5353
If properly configured, this will allow you to run dnsseed in userspace, using the -port=5353 option.
Generate Seed Lists
Bitcoin-seeder is also be used to generate the seed lists that are compiled
into every Bitcoin Cash Node release. It produces the
dnsseed.dump files that are
used as inputs to the scripts in contrib/seeds to generate
the seed lists. To generate seed lists, the seeder should be run continuously
for 30 days or more.