Hello,
I run syncthing locally using the default discovery/relay servers. My firewall reports syncthing reaching out to the following IP address, which I cannot find in the current IPs of the relay servers (https://relays.syncthing.net/). Other IPs were found to be for discovery.syncthing.net - is there a similar list for discovery servers?
What is this IP address called for?
dig data.syncthing.net
;; ANSWER SECTION:
data.syncthing.net. 30 IN CNAME eu-svc.syncthing.net.
eu-svc.syncthing.net. 2513 IN A 141.144.201.57
dig relays.syncthing.net
;; ANSWER SECTION:
relays.syncthing.net. 30 IN A 141.144.201.57
dig upgrades.syncthing.net
;; ANSWER SECTION:
upgrades.syncthing.net. 30 IN CNAME eu-svc.syncthing.net.
eu-svc.syncthing.net. 2191 IN A 141.144.201.57
Looks like this is the current main IP of syncthing’s kubernetes cluster. Several services are hosted on that IP, including (but not limited to):
data.syncthing.net (syncthing usage statistics)relays.syncthing.net (relay pool server)upgrades.sycnthing.net (upgrade checker service)crash.syncthing.net (crash reports)Makes sense, thanks.
Maybe it would be a good idea to call these using the domain e.g. data.syncthing.net so that we can add to the firewall ^(data|relays|upgrades|crash)\.syncthing\.net$ so that the rule will continue working if the IP ever changes.
I looked into the advanced settings, and I see the data, upgrades and crash URLs are by default configured to use the domains. I guess then that call is to relays.syncthing.net for fetching the list of relay server IPs. Is this not configurable?
These IPs should have reverse DNS information configured, that’s often the address firewalls show you. As far as I can see 141.144.201.57 does not have this currently.
I put in a service request with Oracle to have them update it, which is apparently the way it needs to be done there 
Oracle, the law firm with the largest IT department.