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DNS Outage at DigitalOcean

status.digitalocean.com

111–120 of 125 posts

Re: DNS Outage at DigitalOcean

#111
post #99

Earlier quoted context omitted.

You're back online from your perspective. What about all the name servers that have your SOA cached still looking at DO? You're still down for them.

Tough shit, lol. We now have reduced TTL times for future occurrences, but there's nothing we can do for those users who are still experiencing an outage.

Minimum TTL for SOA records on .com is a day. Lowering your A record TTL isn't buying you much in case of DNS hosting failure. Helpful if your site (not dns) needs to move providers though.

Re: DNS Outage at DigitalOcean

#112
post #6

DNS is hard. Very hard. It may seems trivial when it works (hint: it's not), but some of the biggest fuck ups I've seen in my professional life were caused by strange DNS things happening or DNS servers going kaboom. I feel the pain of the DO engineers trying to mitigate this issue. I really do.

BS. DNS is a trivial thing to scale, compared to most other web-scale efforts. Things break when people don't use 20 year old best practices. There is no defense against inexperience and ignorance.

Please help the ignorant and provide a link to a description of those best practices.

Re: DNS Outage at DigitalOcean

#113
post #78

Earlier quoted context omitted.

That's why you use multiple providers.

Unless you use a better resolver than the standard glibc resolver on Linux (e.g. dnsmasq, bind or similar running locally and pointing resolv.conf at it), you appear doomed to slow lookups etc. if your first resolv.conf entry fails, as most of the resolv.conf options that might have helped (if you'd set them) simply don't work or doesn't do anything particularly useful in the versions used in the Linux distro's I've…

unbound is great for this.

Re: DNS Outage at DigitalOcean

#114
post #97

People hating on DO "I'm losing thousands every hour". Well then should have had some failover in place if its that valuable. [1] https://twitter.com/rodrigoespinosa/status/71303563702097100...

How do you fail over your SOA on .com when the minimum TTL is 1 day?

The answer probably is not very helpful but... change the TTL to a lower value? Is it essential to have such a big TTL of 1 day?

Re: DNS Outage at DigitalOcean

#115
post #97

Earlier quoted context omitted.

How do you fail over your SOA on .com when the minimum TTL is 1 day?

The answer probably is not very helpful but... change the TTL to a lower value? Is it essential to have such a big TTL of 1 day?

Sure, have fun convincing Verisign. They're the ones controlling the .com registry. Your TTL values are meaningless to them when it comes to SOA. Minimum 1 day TTL.

Re: DNS Outage at DigitalOcean

#116
post #96

Earlier quoted context omitted.

That's why you use multiple providers.

I'll bite. You can have multiple NS records but only a single SOA. The .com registry minimum TTL for SOA is a day. How in the world would "multiple providers" help you in a 6 hour outage?

You can have multiple NS records. You should have ns records that point to different companies DNS servers, and preferably different continents.

Re: DNS Outage at DigitalOcean

#117
post #96

Earlier quoted context omitted.

I'll bite. You can have multiple NS records but only a single SOA. The .com registry minimum TTL for SOA is a day. How in the world would "multiple providers" help you in a 6 hour outage?

You can have multiple NS records. You should have ns records that point to different companies DNS servers, and preferably different continents.

That's great for NS records. What about SOA?

Re: DNS Outage at DigitalOcean

#118
We have seamless DNS "failover" by running dnsmasq with the all-hosts option on all our servers. It causes dnsmasq to query all at once so if any go down its transparent to our apps. Works perfectly on our 1500 ec2 instances.

Re: DNS Outage at DigitalOcean

#119
post #82

Earlier quoted context omitted.

Only if you don't know what you're doing. The problem with DNS is that it might work even when it is misconfigured, and misconfiguration is the source of strange issues.

I think that we all have areas where we don't know what we're doing. This is one of mine. With all the talk of how obvious/important/easy it is to have a failover in place in case this happens, I'm having trouble finding a good resource about setting up a redundant DNS. Running a droplet on Digital Ocean with Debian and Nginx.

Sounds like we're begging for someone to write a nice blog post for how they set up redundant DNS across multiple providers "the right way"... Sounds like it would hit the front page in short order if anyone is willing to share how they think this should be mitigated, and specifically how to expect common clients to behavior in that case when faced with the various types of outages that may occur!

Re: DNS Outage at DigitalOcean

#120

No offense to anyone here, but what is DO's SLA? Last time I looked, they did not have one. DO is cheap for a reason . And that's the same reason I don't host with them, I can get SLA-backed infrastructure for a reasonable price and would have no excuse to my customers or cofounders.

Looks like they do have one: https://www.digitalocean.com/help/policy/
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