4 ms·
Might be negative caching going on at the sender side. If they can't get a response, they set a TTL on the lack of a response - so future queries don't time out
by sybercecurity 1y ago
Might be negative caching going on at the sender side. If they can't get a response, they set a TTL on the lack of a response - so future queries don't time out but instead immediately return NXDOMAIN. If you immediately tried after restarting your DNS service, it might still be assuming the server is down. Does it still do that after waiting? Like 12-24 hours?
- nvahalik 1y agoSo interestingly... I went back to LinkedIn just a little while ago and there was a different message "mark as working" which I didn't see before. For another provider, I was told I had to contact support as I had been "blacklisted" by Sendgrid and they had to issue a request to unblacklist me.