resolving www.ecb.europa.eu tages ages

[Borja Marcos]

> On 17 Jun 2022, at 13:04, Matus UHLAR - fantomas <uhlar at fantomas.sk> wrote:
> 
> Hello,
> 
> I encountered case where resolution of www.ecb.europa.eu takes long time and I can't find out why.
> 
> I'm trying to find the culprit using dig +trace and resolution times change from < 1 second to > 15 seconds, while response times reported by dig say miliseconds.
> 
> multiple runs of dig seem to fix the issue until I clear named cache.
> (which indicated problem is in DNS, but I still have no idea where)
> 
> I'm out od ideas what to search for.

I tried this at home on my test recursive server (9.18.4) and I found this doing several rndc flush && dig www.ecb.europa.eu.

Whenever these timeouts hit the lame server log I saw resolution times greater than 3 s. By the way, the lame server reporting 
has greatly improved on 9.18 compared to the previous releases.

—
2022-06-20T09:56:34.356+02:00 source=elnuc 2022-06-20T07:56:34.356Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 147.67.12.4#53
2022-06-20T09:56:52.509+02:00 source=elnuc 2022-06-20T07:56:52.509Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 195.99.65.212#53
2022-06-20T10:00:47.834+02:00 source=elnuc 2022-06-20T08:00:47.834Z lame-servers: timed out resolving 'ecb.europa.eu/DS/IN': 195.99.65.212#53
2022-06-20T10:02:18.151+02:00 source=elnuc 2022-06-20T08:02:18.151Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 195.99.65.212#53
2022-06-20T10:02:19.414+02:00 source=elnuc 2022-06-20T08:02:19.413Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 54.154.94.36#53
2022-06-20T10:02:55.365+02:00 source=elnuc 2022-06-20T08:02:55.365Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 147.67.12.4#53
2022-06-20T10:09:14.025+02:00 source=elnuc 2022-06-20T08:09:14.025Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 195.99.65.212#53
2022-06-20T10:09:15.302+02:00 source=elnuc 2022-06-20T08:09:15.302Z lame-servers: timed out resolving 'europa.eu/DNSKEY/IN': 54.154.94.36#53
2022-06-20T10:09:55.377+02:00 source=elnuc 2022-06-20T08:09:55.377Z lame-servers: timed out resolving 'ecb.europa.eu/DS/IN': 54.154.94.36#53
2022-06-20T10:09:56.649+02:00 source=elnuc 2022-06-20T08:09:56.649Z lame-servers: timed out resolving 'ecb.europa.eu/DS/IN': 147.67.12.4#53
2022-06-20T10:14:57.756+02:00 source=elnuc 2022-06-20T08:14:57.756Z lame-servers: timed out resolving 'ecb.europa.eu/DS/IN': 147.67.250.4#53
2022-06-20T10:15:03.435+02:00 source=elnuc 2022-06-20T08:15:03.435Z lame-servers: timed out resolving 'ecb.europa.eu/DS/IN': 147.67.250.4#53
—

I blacklisted the four servers flagging them as “bogus” and my resolutions work now in less than 1 second right after flushing the cache.


42848   | 147.67.12.4      | EC-AS, LU
16509   | 54.154.94.36     | AMAZON-02, US
5400    | 195.99.65.212    | BT, GB
42848   | 147.67.250.4     | EC-AS, LU



—
server 147.67.12.4 {
	bogus yes;
};

server 54.154.94.36 {
	bogus yes;
};

server 195.99.65.212 {
	bogus yes;
};

server 147.67.250.4 {
	bogus yes;
};
—