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What are you talking about? My nginx ssl config is static as well. It looks at a specific path for my certs, which just happens to be a symlink managed my by le

What are you talking about? My nginx ssl config is static as well. It looks at a specific path for my certs, which just happens to be a symlink managed my by letsencrypt tooling. You're going to have to renew anyway. Previously you would have to remember to do that once a year, or maybe once every two years. Now let's ignore the security implications of having certificates that are valid for a year for a moment, and just focus on the actual work. Every year, you have to request a new certificate, wait for your certificate authority, upload the new certificate to the server, reload your webserver, check if everything works. With LE, you do all of that once. You set up the tooling and the cronjob once. You make sure it works once. And you're done. No more hassle.

nly 11y ago
"Once" assuming nothing randomly breaks while you're not looking. What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? What if one of the (Python?) dependencies has a bug or breaks? What if LEs servers are being DDoS'd? Can you enumerate and account for all the failure scenarios? I've already botched things with acme-tiny&LE in several different ways. I'm not claiming these risks are that significant, but given that LE takes just as much time and effort for initial set-up as a standard multi-year cert, if not more, I think the mantra "some risk of failure is more risk of failure than no risk of failure" is something worth baring in mind. And I'm not convinced having 90 day certs is a huge security win. Not only can someone do a lot of damage in 90 days, but your private key (the important bit) can't be rolled every 90 days anyway without integrating your rollover scripts with your HPKP config. If you botch that then your visitors can't come back to your website until the pin expires. Scary. Site ending scary. And if you're not using HPKP then i'm not even going to debate the security pros and cons. On remembering to renew certs... there are many many services out there to send you reminders. Pick 2 or 3 and use them all. Or use a CA that sends reminders. I'm glad LetsEncrypt exists, but let's not treat it like the be-all-and-end-all.
- michaelt 11y ago
  given that LE takes just as much time and effort for initial set-up as a standard multi-year cert I think the LE endgame is that setting up HTTPS will be as easy as setting up SSH - i.e. every server will configure itself right on first launch and keep itself that way. It's just going to take a long time to get there :)
  - nly 11y ago
    > I think the LE endgame is that setting up HTTPS will be as easy as setting up SSH It already is. Use a self-signed cert and ask your visitors via a side channel to tick the box to add an exception. That's the security model of SSH, and has the same assurances. It's just a terrible comparison. We can do better. A better comparison would be with DNSSEC... The way to simplify TLS deployment, while getting a better level security as DV CAs, would have been DANE. DNSSEC has an unfortunate reputation as being hard to setup ("pdnssec secure-zone mydomain" is not hard), but it also has exactly the same X day rollover key problem to solve as LE. Solving it once instead of twice would have made a lot of sense. The symmetries between DNSSEC and LetsEncrypt are striking. Your account key is your KSK. Your cert is your ZSK... but instead of your webserver (in DNSSEC, your DNS server) doing rollover for you, you're depending on a pile of scripts, leaning on an already insecure DNS, and setting it up is still, comparatively, a pita.
    - mapunk 11y ago
      > Use a self-signed cert and ask your visitors via a side channel to tick the box to add an exception. Don't do this. If you have to ask your users to add an SSL exception you're doing it very wrong.
      - _ikke_ 11y ago
        He was comparing the tls equivalent of how SSH works. First time you connect to an ssh server, you have to accept the host key, which most people do not (and in most situations, can not) verify.
    - icebraining 11y ago
- _yy 11y ago
  > What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? That's why I renew them a week in advance. I set up Nagios checks which alert me when a certificate is not renewed. Those were already in place before LetEncrypt since human error is just as likely as a script breaking.
  - guan 11y ago
    I renew every month and have not hit their rate limits. That way, even if the cron job doesn’t fire and I don’t notice, there is another chance a month later.
- pfg 11y ago
  Let's Encrypt renews certificates after 60 days by default, giving you a 30-day grace period for outages, etc. Use a daily cronjob and monitor your certificates. Setup alerts if your certificates are closer than, say, 25 days to expiration. This should cover temporary outages, bugs, etc. - and the monitoring bit is no different from what you should already have even with manual renewal.
- warrenm 11y ago
  run it @weekly it's what I do
- frutiger 11y ago
  > What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? What if one of the (Python?) dependencies has a bug or breaks? What if LEs servers are being DDoS'd? Can you enumerate and account for all the failure scenarios? I run my cron job[1] every hour. It checks for the expiry of my existing set of certificates and has a configurable parameter as to how soon before expiry to renew them. [1] https://github.com/frutiger/concorde https://github.com/frutiger/concorde
- tokenizerrr 11y ago
  Nagios will tell me when my certificate is a month within expiring. This is a standard nagios plugin. The cronjob runs nightly, checks if renewal is necessary (once a month, certificates valid for 3 months, so will renew when 2 months are still left) and then does its thing.
novaleaf 11y ago
I think you are underestimating the cognitive burden this added complexity puts on your ops person (maybe yourself) I know for me, it was a choice between farting around with lets-encrypt for hours, or a $40 wildcard cert. so I went with the $40/year cert instead. There are just too many choices for lets-encrypt with no super-simple how-to for people who don't know this stuff (like myself).
- metafunctor 11y ago
  I thought the same, until I actually took it upon myself to actually try LE. 15 minutes later, I had all my sites on LE, automatic renewal configured. I'm looking forward not having to sign in to some website, cut'n'paste certificates around, convert to/from PEM, figuring out what the correct chain is this time, etc.
  - novaleaf 11y ago
    I guess I'm stupid then, because I spent more than an hour trying to figure an easy way to add these to my auto-provisioned servers before giving up and using the static cert instead.
antouank 11y ago
Can you update the certificate without taking down your nginx server? I assume you need port 443 for LE to verify your domain, right? Can you use a different port?
- warrenm 11y ago
  sure - run the renewal from a different server
  - lfam 11y ago
    You can do it on the same server without downtime by using the "webroot" method of the LE client.
- lfam 11y ago
  Yes, use the "webroot" method of the official Let's Encrypt client.
  - antouank 11y ago
    I see, thanks. I use the docker container "version", so I assume I have to somehow mount a volume to the container, that's also accessible from my nginx ( or whatever ) container, so it can serve the static file LE creates. Is there something more to it?
- vincentleeuwen 11y ago
  https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-14-04#step-4-—-set-up-auto-renewal https://www.digitalocean.com/community/tutorials/how-to-secu...

nly 11y ago

"Once" assuming nothing randomly breaks while you're not looking. What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? What if one of the (Python?) dependencies has a bug or breaks? What if LEs servers are being DDoS'd? Can you enumerate and account for all the failure scenarios? I've already botched things with acme-tiny&LE in several different ways. I'm not claiming these risks are that significant, but given that LE takes just as much time and effort for initial set-up as a standard multi-year cert, if not more, I think the mantra "some risk of failure is more risk of failure than no risk of failure" is something worth baring in mind. And I'm not convinced having 90 day certs is a huge security win. Not only can someone do a lot of damage in 90 days, but your private key (the important bit) can't be rolled every 90 days anyway without integrating your rollover scripts with your HPKP config. If you botch that then your visitors can't come back to your website until the pin expires. Scary. Site ending scary. And if you're not using HPKP then i'm not even going to debate the security pros and cons. On remembering to renew certs... there are many many services out there to send you reminders. Pick 2 or 3 and use them all. Or use a CA that sends reminders. I'm glad LetsEncrypt exists, but let's not treat it like the be-all-and-end-all.

michaelt 11y ago
given that LE takes just as much time and effort for initial set-up as a standard multi-year cert I think the LE endgame is that setting up HTTPS will be as easy as setting up SSH - i.e. every server will configure itself right on first launch and keep itself that way. It's just going to take a long time to get there :)
- nly 11y ago
  > I think the LE endgame is that setting up HTTPS will be as easy as setting up SSH It already is. Use a self-signed cert and ask your visitors via a side channel to tick the box to add an exception. That's the security model of SSH, and has the same assurances. It's just a terrible comparison. We can do better. A better comparison would be with DNSSEC... The way to simplify TLS deployment, while getting a better level security as DV CAs, would have been DANE. DNSSEC has an unfortunate reputation as being hard to setup ("pdnssec secure-zone mydomain" is not hard), but it also has exactly the same X day rollover key problem to solve as LE. Solving it once instead of twice would have made a lot of sense. The symmetries between DNSSEC and LetsEncrypt are striking. Your account key is your KSK. Your cert is your ZSK... but instead of your webserver (in DNSSEC, your DNS server) doing rollover for you, you're depending on a pile of scripts, leaning on an already insecure DNS, and setting it up is still, comparatively, a pita.
  - mapunk 11y ago
    > Use a self-signed cert and ask your visitors via a side channel to tick the box to add an exception. Don't do this. If you have to ask your users to add an SSL exception you're doing it very wrong.
    - _ikke_ 11y ago
      He was comparing the tls equivalent of how SSH works. First time you connect to an ssh server, you have to accept the host key, which most people do not (and in most situations, can not) verify.
  - icebraining 11y ago
_yy 11y ago
> What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? That's why I renew them a week in advance. I set up Nagios checks which alert me when a certificate is not renewed. Those were already in place before LetEncrypt since human error is just as likely as a script breaking.
- guan 11y ago
  I renew every month and have not hit their rate limits. That way, even if the cron job doesn’t fire and I don’t notice, there is another chance a month later.
pfg 11y ago
Let's Encrypt renews certificates after 60 days by default, giving you a 30-day grace period for outages, etc. Use a daily cronjob and monitor your certificates. Setup alerts if your certificates are closer than, say, 25 days to expiration. This should cover temporary outages, bugs, etc. - and the monitoring bit is no different from what you should already have even with manual renewal.
warrenm 11y ago
run it @weekly it's what I do
frutiger 11y ago
> What if your cronjob doesn't fire? What if LEs script has a bug and you're not up to date? What if one of the (Python?) dependencies has a bug or breaks? What if LEs servers are being DDoS'd? Can you enumerate and account for all the failure scenarios? I run my cron job[1] every hour. It checks for the expiry of my existing set of certificates and has a configurable parameter as to how soon before expiry to renew them. [1] https://github.com/frutiger/concorde https://github.com/frutiger/concorde
tokenizerrr 11y ago
Nagios will tell me when my certificate is a month within expiring. This is a standard nagios plugin. The cronjob runs nightly, checks if renewal is necessary (once a month, certificates valid for 3 months, so will renew when 2 months are still left) and then does its thing.

novaleaf 11y ago

I think you are underestimating the cognitive burden this added complexity puts on your ops person (maybe yourself) I know for me, it was a choice between farting around with lets-encrypt for hours, or a $40 wildcard cert. so I went with the $40/year cert instead. There are just too many choices for lets-encrypt with no super-simple how-to for people who don't know this stuff (like myself).

metafunctor 11y ago
I thought the same, until I actually took it upon myself to actually try LE. 15 minutes later, I had all my sites on LE, automatic renewal configured. I'm looking forward not having to sign in to some website, cut'n'paste certificates around, convert to/from PEM, figuring out what the correct chain is this time, etc.
- novaleaf 11y ago
  I guess I'm stupid then, because I spent more than an hour trying to figure an easy way to add these to my auto-provisioned servers before giving up and using the static cert instead.

antouank 11y ago

Can you update the certificate without taking down your nginx server? I assume you need port 443 for LE to verify your domain, right? Can you use a different port?

warrenm 11y ago
sure - run the renewal from a different server
- lfam 11y ago
  You can do it on the same server without downtime by using the "webroot" method of the LE client.
lfam 11y ago
Yes, use the "webroot" method of the official Let's Encrypt client.
- antouank 11y ago
  I see, thanks. I use the docker container "version", so I assume I have to somehow mount a volume to the container, that's also accessible from my nginx ( or whatever ) container, so it can serve the static file LE creates. Is there something more to it?
vincentleeuwen 11y ago
https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-14-04#step-4-—-set-up-auto-renewal https://www.digitalocean.com/community/tutorials/how-to-secu...