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Archive for the ‘Cloud’ Category

Setting up a GitLab project so it is served over https as a gitlab.io and a custom subdomain

Posted by jpluimers on 2022/05/05

Last week, I posted about Setting up a GitHub project so it is served over https as a custom github.io subdomain.

Today it’s the equivalent, but on GitLab.

Why GitLab? Two major reasons: unlike GitHub:

  1. it’s open source
  2. provides way more granular control over permissions
  3. allows a hierarchy of repositories on which you can specify that permission control

Already 2. and 3. combined are a huge advantage, though we will see that 3. also makes some of the subcases (hosting as user.gitlab.io from account gitlab.com/user where user is your username) is harder than the similar user.github.io, github.com/user combo.

So here we go, starting with a similar set of links:

The goal is to have

  1. page projects as or under wiert.gitlab.io (like wiert.gitlab.io/wiert)
  2. a gitlabstatus.wiert.me plain html (or maybe markdown) page project that eventually will show some status information (kind of like status.gitlab.com, but for different things).

The beauty of GitLab is that it supports hierarchies of repositories through groups and subgroups, so I already had these subgroups hoping they would cover both the first and second kind of page projects:

Steps I did

Since there are quite a few links above, here are the steps I took from my gitlab.com/wiert account and gitlab.com/wiert.me group.

Steps for wiert.gitlab.io/wiert

  1. For wiert.gitlab.io/wiert, try A (failed in part, and therefore interesting to understand why):
    1. Under leaf group gitlab.com/wiert.me/public/web/sites/gitlab.io, created a new GitLab repository
    2. Chose “Create from template”
    3. Chose the template “Pages/Plain HTML”
    4. Named the project “wiert” (with slug “wiert“) so it would appear at gitlab.com/wiert.me/public/web/sites/gitlab.io/wiert
    5. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    6. Now I got in a confusing situation as the page indicated “There are currently no pipelines.”, but an enabled blue “Run pipeline” button:
      By default there is no CI/CD pipeline, but there is an enabled blue "Run pipeline" button: confusing.

      By default there is no CI/CD pipeline, but there is an enabled blue “Run pipeline” button: confusing.

    7. Clicked the “Run pipeline” button nonetheless, and that created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    8. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job and deployed the page.
    9. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wiert.me.gitlab.io/public/web/sites/gitlab.io/wiert/ and https://wiert.me.gitlab.io/public/web/sites/gitlab.io/wiert/
       Warning: When using Pages under the general domain of a GitLab instance (gitlab.io), you cannot use HTTPS with sub-subdomains.

      Warning: When using Pages under the general domain of a GitLab instance (gitlab.io), you cannot use HTTPS with sub-subdomains.

      The sites do work (see the [Archive.is http version] and [Archive.is https version]), but the HTTPS fails because wiert.me.gitlab.io does not match the SANs (Subject Alternative Names) in the certificate: *.gitlab.io, gitlab.io

  2. For wiert.gitlab.io/wiert, try B (failed, and therefore interesting to understand why):
    1. In my my groups gitlab.com/dashboard/groups, added a new group wiert
    2. Added subgroups until the leaf gitlab.com/wiert/public/web/sites/gitlab.io which as URL is gitlab.com/wier1/public/web/sites/gitlab.io because user account wiert already occupies gitlab.com/wiert.
    3. Under leaf group gitlab.com/wier1/public/web/sites/gitlab.io, created a new GitLab repository
    4. Chose “Create from template”
    5. Chose the template “Pages/Plain HTML”
    6. Named the project “wiert” (with slug “wiert“) so it would appear at gitlab.com/wiert.me/public/web/sites/gitlab.io/wiert
    7. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    8. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    9. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    10. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    11. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wier1.gitlab.io/public/web/sites/gitlab.io/wiert and https://wier1.gitlab.io/public/web/sites/gitlab.io/wiert.
      Bummer: again not the wiert.gitlab.io/wiert I hoped for
      The sites do work (see the [Archive.is http version] and [Archive.is https version]). The HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

    12. If a user wiert exists and occupies gitlab.com/wiert, then a group named wiert cannot occupy gitlab.com/wiert, and therefore a project named wiert within that group won’t be deployed to wiert.gitlab.io/wiert.
      Maybe this can be shortened like “if there is a user wiert, then no group named wiert cannot be used to contain a project named wiert to host as wiert.gitlab.io/wiert“.
      Let’s find out!
  3. For  wiert.gitlab.io/wiert, try C (success, steps 1, 3, 4, 7 and 8 were the key ones):
    1. In my user gitlab.com/wiert, created a new GitLab repository
    2. Chose “Create from template”
    3. Chose the template “Pages/Plain HTML”
    4. Named the project “wiert” (with slug “wiert“) so it would appear at gitlab.com/wiert
    5. The odd but cool thing is that the actual project now ended up at gitlab.com/wiert/wiert:
    6. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    7. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    8. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    9. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    10. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wiert.gitlab.io/wiert/ and https://wiert.gitlab.io/wiert/.
      Success: finally the wiert.gitlab.io/wiert I hoped for:

      Success: published at https://wiert.gitlab.io/wiert/

      Success: published at https://wiert.gitlab.io/wiert/

      The sites do work fine (see the [Archive.is http version] and [Archive.is https version]). The HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

Steps for wiert.gitlab.io

  1. For wiert.gitlab.io, try A (failed, and therefore interesting to understand why):
    1. Under leaf group gitlab.com/wiert.me/public/web/sites/gitlab.io, created a new GitLab repository
    2. Chose “Create from template”
    3. Chose the template “Pages/Plain HTML”
    4. Named the project “wiert.gitlab.io” (with slug “wiert.gitlab.io“) so it would appear at gitlab.com/wiert.me/public/web/sites/gitlab.io/wiert.gitlab.io
    5. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    6. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    7. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    8. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    9. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wiert.me.gitlab.io/public/web/sites/gitlab.io/wiert.gitlab.io and https://wiert.me.gitlab.io/public/web/sites/gitlab.io/wiert.gitlab.io.
      Failure: not the wiert.gitlab.io I hoped for.

      The sites do work (see the [Archive.is http version] and [Archive.is https version]), but the HTTPS fails because wiert.me.gitlab.io does not match the SANs (Subject Alternative Names) in the certificate: *.gitlab.io, gitlab.io. The HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

  2. For wiert.gitlab.io, try B (failed, and therefore interesting to understand why):
    1. Under leaf group gitlab.com/wier1/public/web/sites/gitlab.io, created a new GitLab repository
    2. Chose “Create from template”
    3. Chose the template “Pages/Plain HTML”
    4. Named the project “wiert.gitlab.io” (with slug “wiert.gitlab.io“) so it would appear at gitlab.com/wier1/public/web/sites/gitlab.io/wiert.gitlab.io
    5. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    6. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    7. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    8. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    9. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wier1.gitlab.io/public/web/sites/gitlab.io/wiert.gitlab.io and https://wier1.gitlab.io/public/web/sites/gitlab.io/wiert.
      Bummer: again not the wiert.gitlab.io I hoped for
      The sites do work (see the [Archive.is http version] and [Archive.is https version]). The HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

    10. Try A and B were almost identical to wiert.gitlab.io/wiert try A and B, so let’s see if the solution C for that also works for us:
  3. For wiert.gitlab.io, try C (success, steps 1, 3, 4, 7 and 9 were the key ones)
    1. In my user gitlab.com/wiert, created a new GitLab repository
    2. Chose “Create from template”
    3. Chose the template “Pages/Plain HTML”
    4. Named the project “wiert.gitlab.io” (with slug “wiert.gitlab.io“) so it would appear at gitlab.com/wiert/wiert.gitlab.io.
    5. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    6. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    7. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    8. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    9. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wiert.gitlab.io/ and https://wiert.gitlab.io/.
      Success: finally the wiert.gitlab.io I hoped for with working sites (see the [Archive.is http version] and [Archive.is https version]).
    10. Note the HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

Steps for gitlabstatus.wiert.me

Having learned from the GitHub githubstatus.wiert.me procedure (where I had to wait a long time for the default *.wiert.me domain mapping timeout and the githubstatus.wiert.me DNS CNAME record to become effective), I started on the DNS CNAME record side which is documented at [Wayback] Custom domains and SSL/TLS certificates: Section 3. Set up DNS records for Pages: For subdomains | GitLab:

Subdomains (subdomain.example.com) require:

  • A DNS CNAME record pointing your subdomain to the Pages server.
  • A DNS TXT record to verify your domain’s ownership.
From DNS Record To
subdomain.example.com CNAME namespace.gitlab.io
_gitlab-pages-verification-code.subdomain.example.com TXT gitlab-pages-verification-code=00112233445566778899aabbccddeeff

Note that, whether it’s a user or a project website, the CNAME should point to your Pages domain (namespace.gitlab.io), without any /project-name.

DNS CNAME record pointing to GitLab.com project

The value for the TXT record is only known after you created the pages project, but the value for the CNAME record is known beforehand:

From DNS Record To
gitlabstatus.wiert.me CNAME namespace.gitlab.io

So let’s see if I can do this in one try, with these steps:

  1. For gitlabstatus.wiert.me, try A (success, steps 1, 3, 4, 7 and 9 were the key ones)
    1. In my DNS settings of the wiert.me domain, created a CNAME record from gitlabstatus.wiert.me to namespace.gitlab.io:

      gitlabstatus.wiert.me CNAME record pointing to namespace.gitlab.io

      gitlabstatus.wiert.me CNAME record pointing to namespace.gitlab.io

    2. Under leaf group gitlab.com/wiert.me/public/web/sites/wiert.me, created a new GitLab repository
    3. Chose “Create from template”
    4. Chose the template “Pages/Plain HTML”
    5. Named the project “gitlabstatus.wiert.me” (with slug “gitlabstatus.wiert.me“) so it would appear at gitlab.com/wiert.me/public/web/sites/wiert.me/gitlabstatus.wiert.me
    6. From the left sidebar, navigated to your project’s “CI/CD”, then “Pipelines”
    7. Again there was “There are currently no pipelines.”, but an enabled blue “Run pipeline” button, which I clicked
    8. That created [Wayback/Archive.is] a pipeline asking for parameters (that already had correct default values) and revealed a new blue “Run pipeline” button.
    9. Clicked that new “Run pipeline button” which created [Wayback/Archive.is] a job deployed the page.
    10. From the left sidebar, navigated to “Settings”, then “Pages” to get the links to the pages site: http://wiert.me.gitlab.io/public/web/sites/wiert.me/gitlabstatus.wiert.me and https://wiert.me.gitlab.io/public/web/sites/wiert.me/gitlabstatus.wiert.me.
      Intermediate success: working sites (see the [Archive.is http version] and [Archive.is https version]).
    11. Now it is time to get the DNS CNAME record from gitlabstatus.wiert.me to namespace.gitlab.io into operation by clicking the “New Domain” button:
      "New Domain" button in the "Pages" settings.

      “New Domain” button in the “Pages” settings.

    12. There I filled in the correct gitlabstatus.wiert.me domain name, then pressed the “Create New Domain” button:

      New domain becomes gitlabstatus.wiert.me

      New domain becomes gitlabstatus.wiert.me

    13. Then a page appeared voiding the DNS CNAME work I already did: the documentation is clearly wrong as these are the two DNS record entries to be made as shown by gitlab.com/wiert.me/public/web/sites/wiert.me/gitlabstatus.wiert.me/pages/domains/gitlabstatus.wiert.me:
      Correct instructions for the DNS records to get gitlabstatus.wiert.me working

      Correct instructions for the DNS records to get gitlabstatus.wiert.me working

      Subdomains (gitlabstatus.wiert.me) require:

      • A DNS CNAME record pointing your subdomain to the Pages server.
      • A DNS TXT record to verify your domain’s ownership.
      From DNS Record To
      gitlabstatus.wiert.me CNAME wiert.me.gitlab.io.
      _gitlab-pages-verification-code.gitlabstatus.wiert.me TXT gitlab-pages-verification-code=c5619988d386b1a36c253ce05db55dbb

      Basically the whole namespace.gitlab.io part of the documentation is a placeholder for the actual namespace that belongs to the leaf group the pages project is in (in my case wiert.me).

      So this is the new DNS entry, for which I had to wait until the DNS TTL to time out and effectuate:
      New DNS gitlabstatus.wiert.me CNAME record pointing to wiert.me.gitlab.io

      New DNS gitlabstatus.wiert.me CNAME record pointing to wiert.me.gitlab.io

      Note that this DNS administrative interface from WordPress.com does omit the final period of the CNAME destination (officially this would be wiert.me.gitlab.io.)

    14. After the CNAME DNS record, I also made the TXT DNS record:
      New DNS TXT record for verification of gitlabstatus.wiert.me

      New DNS TXT record for verification of gitlabstatus.wiert.me

      Then I waited a little for the DNS TXT record to be saved and try the verification of the TXT record.

    15. Even then, verification took some time. I had to click the refresh button a few times before verification succeeded:
      The DNS TXT record for gitlabstatus.wiert.me finally got verified

      The DNS TXT record for gitlabstatus.wiert.me finally got verified

    16. Now I could press blue “Save Changes” button below and waited for the CNAME record DNS TTL to expire so I could check the domain and – hopefully – the TLS certificate to be requested by Let’s Encrypt:
      After the gitlabstatus.wiert DNS TXT record got verified, I could save the domain information

      After the gitlabstatus.wiert DNS TXT record got verified, I could save the domain information

    17. After the old CNAME record DNS TTL expired and the new CNAME record came into effect, the domain became available as http://gitlabstatus.wiert.me/:
      Waiting for gitlabstatus.wiert.me to become active

      Waiting for gitlabstatus.wiert.me to become active

    18. After verification, the “Domains (1)” bit changed from this:
      Domain gitlabstatus.wiert.me information before verification

      Domain gitlabstatus.wiert.me information before verification

      to this:

      Domain gitlabstatus.wiert.me information after verification

      Domain gitlabstatus.wiert.me information after verification

    19. In the mean time, also the TLS certificate got issued by Let’s Encrypt, so the final sites now both worked: http://gitlabstatus.wiert.me/ and https://gitlabstatus.wiert.me/.
    20. Success: finally the gitlabstatus.wiert.me I hoped for with working sites (see the [Archive.is http version] and [Archive.is https version] for the wiert.me domain, and [Archive.is http version] and [Archive.is https version] for the wiert.me domain).
    21. Note the HTTP does not redirect to the HTTP version, as I did not tick the

      ☐ Force HTTPS (requires valid certificates)

In retrospect, this could have been shorter when I had done the DNS part later, which is contrary to how to do this with GitHub.

Conclusion

The conclusion seems this:

Gitlab Page repositories to be published as or under wiert.gitlab.io need to reside directly under user wiert. Having them reside under a different group like wiert or wiert.me won’t work.

Or in more generic terms:

When creating pages as user.gitlab.io you have to put your pages projects directly under your user account gitlab.com/user.

Putting them under groups or leaf groups fails, no matter if the (leaf) group is named user or otherwise.

In addition, you can add custom domains to any Gitlab repository (even one that never stated out as a GitLab Pages repository). It will work as soon as the domain DNS mapping is setup through both a CNAME mapping record and TXT verification record.

The steps for this in your GitLab repository are:

  1. Ensure you have a valid .gitlab-ci.yml file at the root of your repository; I used the [Wayback/Archive.is] one from [Wayback/Archive] GitLab Pages examples / plain-html · GitLab as my site is purely static
  2. Ensure you have a valid index.html file in the public directory of your repository, similar to [Wayback/Archive] GitLab Pages examples / plain-html · GitLab
  3. When both 1. and 2. are committed in your repository at GitLab, then it will automatically be deployed to a docker container on gitlab.io, which allows the outside world to visit your GitHub Pages sie, and the Let’s Encrypt Certificate to be generated (and prevents this error: [Wayback/Archive] GitLab Pages integration with Let’s Encrypt | GitLab: “Something went wrong while obtaining the Let’s Encrypt certificate”).
  4. Under “Settings” -> “Pages”, add a new domain name to the repository: now it automatically becomes a GitLab Pages repository.
  5. When adding the domain, the settings page will show both a DNS CNAME record and DNS TXT record; ensure both are applied on your primary DNS name server and replicated to all authoritative DNS name servers.
  6. Save the new page.
  7. Check if the page is available on the new domain you added.
  8. Optionally under “Settings” -> “Pages” enable the “Force HTTPS (requires valid certificates)” option and save.

TLS information

Note: I saved the TLS information – including certificates here:

More about the Let’s Encrypt certificates at [Wayback] Chain of Trust – Let’s Encrypt:

–jeroen

Read the rest of this entry »

Posted in Cloud, Communications Development, Development, DNS, Encryption, GitLab, Hosting, HTML, HTTPS/TLS security, Infrastructure, Internet, Internet protocol suite, Let's Encrypt (letsencrypt/certbot), Power User, Software Development, Source Code Management, TCP, TLS, Web Development | Leave a Comment »

Setting up a GitHub project so it is served over https as a github.io and a custom subdomain

Posted by jpluimers on 2022/04/27

Some links that helped me getting this working:

Read the rest of this entry »

Posted in Cloud, Cloudflare, Communications Development, Development, Encryption, GitHub, HTML, HTTP, HTTPS/TLS security, Infrastructure, Internet protocol suite, Let's Encrypt (letsencrypt/certbot), Power User, Security, Software Development, Source Code Management, TCP, TLS, Web Development | Leave a Comment »

Perkeep lets you permanently keep your stuff, for life.

Posted by jpluimers on 2022/03/30

For my link archive: [Wayback] Perkeep

Via [Wayback] bradfitz – Joining Tailscale: Simplifying Networking, Authentication, and Authorization (which has many interesting linkis, including [Archive.is] bradfitz/homelab: Brad’s homelab setup)

–jeroen

Posted in Cloud, Hardware, Infrastructure, Network-and-equipment, Perkeep, Power User, Storage, Tailscale, VPN, Wireguard | Leave a Comment »

Some links on using and updating Let’s Encrypt certificates for internal servers

Posted by jpluimers on 2022/02/01

Sometimes it is easier to have current and public CA signed TLS certificates for internal servers than to setup and maintain an internal CA and register it on all affected browsers (including mobile phones).

One of my reasons to investigate this is that Chrome refuses to save credentials on servers that have no verifiable TLS certificate, see my post Some links on Chrome not prompting to save passwords (when Firefox and Safari do) about a week ago.

Below are some links for my link archive that hopefully will allow me to do this with Let’s Encrypt (msot via [Wayback/Archive] letsencrypt for internal servers – Google Search):

Read the rest of this entry »

Posted in Cloud, Cloudflare, Development, Encryption, ESXi6, ESXi6.5, ESXi6.7, ESXi7, Fritz!, Fritz!Box, Fritz!WLAN, Infrastructure, Internet, Let's Encrypt (letsencrypt/certbot), Power User, Security, Software Development, Virtualization, VMware, VMware ESXi, Web Development | Leave a Comment »

Katie Anderson on Twitter: “Saw this on Facebook and it’s my new favorite PaaS (Pizza as a Service) breakdown”

Posted by jpluimers on 2021/11/30

Legacy/IaaS/PaaS/SaaS explained by “Pizza as a service”: from home made, take and bake, pizza delivery to full dining out.

[Archive.is] Katie Anderson on Twitter: “Saw this on Facebook and it’s my new favorite PaaS (Pizza as a Service) breakdown https://t.co/INKKG9UOAK” / Twitter

–jeroen

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Posted in Cloud, Conference Topics, Conferences, Development, Event, Infrastructure, Software Development, Systems Architecture | Leave a Comment »

Using Google/Cloudflare/central DNS can bite you with large downloads

Posted by jpluimers on 2021/10/22

If you think download speeds are slow for large downloads (or multi-media playback is slow or quality is low) on a fast link, then consider your DNS.

Many people report that using one of the centralised DNS services (like Google/Cloudflare/…) causes slowness because they direct CDN lookups to a small pool of servers that get overloaded.

Some links:

Via [WayBack] How to check whether DNS is working through a browser? – Super User

Google DNS also allows for interactive querying, for example [WayBack] Google Public DNS

Read the rest of this entry »

Posted in Cloud, Cloudflare, DNS, Hardware, Infrastructure, Internet, Network-and-equipment, Power User | Leave a Comment »

Links to learn more about infrastructure.

Posted by jpluimers on 2021/10/14

For my link archive; [Archive.is] .DS_Storoz on Twitter: “Alright, I’m rage-quitting the frontend, moving into infrastructure. (Seriously.) Where is my community for this? Who do I follow? What conferences do I go to? Please and thanks and RT!”

Keywords:

  • Terraform, Docker, Kubernetes, AWS!
  • Systems Performance, Google SRE book, DDIA
  • the DORA report
  • b0rk

–jeroen

Posted in Amazon S3, Amazon SES, Amazon.com/.de/.fr/.uk/..., AWS Amazon Web Services, Cloud, Containers, Docker, Infrastructure, Kubernetes (k8n), Power User | Leave a Comment »

For my link archive: DNS over https

Posted by jpluimers on 2021/09/02

DNS over HTTPS

For my link archive:

JSON DNS output

Some DNS over HTTSP providers support dns-json, which Cloudflare delivers non-pretty printed.

Read the rest of this entry »

Posted in Cloud, Cloudflare, Communications Development, Development, DNS, Encryption, HTTP, https, HTTPS/TLS security, Infrastructure, Internet, Internet protocol suite, Power User, Security, Software Development, TCP, TLS | Leave a Comment »

On my list of things to try: Amazon SES for outbound/inbound email handling

Posted by jpluimers on 2021/08/10

SES mail servers at the time of writing

*n*x:

# nslookup -type=TXT amazonses.com | grep "v=spf1"
amazonses.com   text = "v=spf1 ip4:199.255.192.0/22 ip4:199.127.232.0/22 ip4:54.240.0.0/18 ip4:69.169.224.0/20 ip4:76.223.180.0/23 ip4:76.223.188.0/24 ip4:76.223.189.0/24 ip4:76.223.190.0/24 -all"I

Windows

C:\>nslookup -type=TXT amazonses.com | find "v=spf1"
Non-authoritative answer:
        "v=spf1 ip4:199.255.192.0/22 ip4:199.127.232.0/22 ip4:54.240.0.0/18 ip4:69.169.224.0/20 ip4:76.223.180.0/23 ip4:76.223.188.0/24 ip4:76.223.189.0/24 ip4:76.223.190.0/24 -all"

These addresses use a compact CIDR notation to denote ranges of networks containing ranges of network IPv4 addresses.

CIRD processing to sendmail access file

(this is linux sendmail only)

Converting the nslookup outout to a CIDR based sendmail /etc/mail/access excerpt goes via a pipe sequence of multiple sed commands:

# nslookup -type=TXT amazonses.com | grep "v=spf1" | sed 's/\(^.*"v=spf1 ip4:\| -all"$\)//g' | sed 's/\ ip4:/\n/g' | xargs -I {} sh -c "prips {} | sed 's/$/\tRELAY/g'"
199.255.192.0   RELAY
199.255.192.1   RELAY
...
76.223.190.254  RELAY
76.223.190.255  RELAY

What happens here is this:

  1. Filter out only spf1 records using grep.
  2. Remove the head (.*v=spf1 ip4:) and tail ( -all") of the output, see [WayBack] use of alternation “|” in sed’s regex – Super User.
  3. Replaces all ip4: with newlines (so the output get split over multiple lines), see [WayBack] linux – splitting single line into multiple line in numbering format using awk – Stack Overflow.
  4. Convert the CIDR notation to individual IP addresses (as sendmail cannot handle CIDR),
    1. This uses a combination of xargs with the  sh trick to split the CIDR list into separate arguments, and prips (which prints the IP addresses for a CIDR); see:
    2. Alternatively, use
  5. Replaces all end-of-line anchor ($) with a tab followed by RELAY, see

You can append the output of this command to /etc/mail/access, then re-generate /etc/mail/access.db and restart sendmail; see for instance [WayBack] sendmail access.db by example | LinuxWebLog.com.

Without the xargs, the output would look like this:

# nslookup -type=TXT amazonses.com | grep "v=spf1" | sed 's/\(^.*"v=spf1 ip4:\| -all"$\)//g' | sed 's/\ ip4:/\n/g'
199.255.192.0/22
199.127.232.0/22
54.240.0.0/18
69.169.224.0/20
76.223.180.0/23
76.223.188.0/24
76.223.189.0/24
76.223.190.0/24

Via

–jeroen

Posted in *nix, *nix-tools, Amazon SES, Amazon.com/.de/.fr/.uk/..., Cloud, Communications Development, Development, Infrastructure, Internet protocol suite, Power User, sendmail, SMTP, Software Development | Leave a Comment »

Firefox: disable DNS over HTTPS (which they call TTR)

Posted by jpluimers on 2021/08/03

There are many reasons to disable DNS over HTTPS (DoH), of which enough are discussed in the links below.

Disabling DoH always talks about setting TTR (the abbreviation Mozilla uses for it) to 5 (like [WayBack] Thread by @isotopp: “Firefox is about to break DNS by enabling DNS-over-HTTP by default […]”), but hardly ever explains the meaning of 5, or any other potential values.

After some searching, I found [WayBack] Firefox disable trr | Knowledge Base:

  • 0: Off by default
  • 1: Firefox chooses faster
  • 2: TRR default w/DNS fallback
  • 3: TRR only mode
  • 5: Disabled

I imagine the setting we’re all looking for is: user_pref(“network.trr.mode”, 5); (emphasis mine)

It pointed me to [WayBack] Trusted Recursive Resolver – MozillaWiki:

Read the rest of this entry »

Posted in Cloud, Cloudflare, Communications Development, Development, DNS, Firefox, Infrastructure, Internet protocol suite, Power User, TCP, Web Browsers | Leave a Comment »