diff --git a/_posts/2020/08/2020-08-19-introducing-consulting.md b/_posts/2020/08/2020-08-19-introducing-consulting.md
index c3066bd0eb5fa85c9847cafdfdad7b613a212287..dd9c93dc80b32d0a308a40b9a06b06020113a917 100644
--- a/_posts/2020/08/2020-08-19-introducing-consulting.md
+++ b/_posts/2020/08/2020-08-19-introducing-consulting.md
@@ -53,7 +53,7 @@ HIFIS Consulting is free, and available to any group or team that falls under th
 All you need to do is fill out the form on our [**consulting page**][hifis/consulting],
 and we will be in touch as soon as possible.
 
-[hifis/consulting]: <https://software.hifis.net/services/consulting>
+[hifis/consulting]: {% link services/consulting.html %}
 
 <br />
 
@@ -63,6 +63,6 @@ and we will be in touch as soon as possible.
     If you work for a Helmholtz-affilliated institution, and think that something like this would be useful to you, send us an e-mail at
     <strong><a href="mailto:{{site.contact_mail}}">{{site.contact_mail}}</a></strong>,
     or fill in our
-    <strong><a href="https://software.hifis.net/services/consulting#consultation-request-form">consultation request form</a></strong>.
+    <strong><a href="{% link services/consulting.html %}#consultation-request-form">consultation request form</a></strong>.
   </p>
 </div>
diff --git a/_posts/2020/09/2020-09-23-getting-started-with-docker-1.md b/_posts/2020/09/2020-09-23-getting-started-with-docker-1.md
index af79f1eb6de717b675a87d51e464a9e1117f6c4c..549b379d7a7305ad37a22c04e1a857dec2f09bed 100644
--- a/_posts/2020/09/2020-09-23-getting-started-with-docker-1.md
+++ b/_posts/2020/09/2020-09-23-getting-started-with-docker-1.md
@@ -4,7 +4,7 @@ date: 2020-09-23
 authors:
     - frere
 layout: blogpost
-title_image: docker-cover.jpg
+title_image: docker-cover.png
 categories:
     - tutorial
 tags:
@@ -114,6 +114,12 @@ this is essentially just the core part of Docker that runs containers.
 The installation instructions for Mac, Windows, and Linux are available at the [Get Docker](https://docs.docker.com/get-docker/) page --
 if you want to follow along with the rest of these commands, feel free to complete those installation instructions, and then come back here.
 
+{:.summary}
+> N.B. On most Linux distributions, you will need to also follow the post-installation steps
+> (linked at the bottom of the installation page and [here](https://docs.docker.com/engine/install/linux-postinstall/))
+> in order to run the `docker` command without `sudo` as a non-root user.
+> If you're getting errors about invalid permissions when running any of the following commands, this is probably the issue you are facing.
+
 [^3]:
     Why?
     As I mentioned in the previous footnote,
@@ -286,7 +292,7 @@ View part two [here]({% post_url 2020/09/2020-09-25-getting-started-with-docker-
     If you work for a Helmholtz-affiliated institution, and think that this would be useful to you, send us an e-mail at
     <strong><a href="mailto:{{site.contact_mail}}">{{site.contact_mail}}</a></strong>,
     or fill in our
-    <strong><a href="https://software.hifis.net/services/consulting#consultation-request-form">consultation request form</a></strong>.
+    <strong><a href="{% link services/consulting.html %}#consultation-request-form">consultation request form</a></strong>.
   </p>
 </div>
 
diff --git a/_posts/2020/09/2020-09-25-getting-started-with-docker-2.md b/_posts/2020/09/2020-09-25-getting-started-with-docker-2.md
index cba42ee734ea1c344e67b0e3c5f2bb7152422d31..11ced35e258f17314aaa49af9b0da984c33b07a4 100644
--- a/_posts/2020/09/2020-09-25-getting-started-with-docker-2.md
+++ b/_posts/2020/09/2020-09-25-getting-started-with-docker-2.md
@@ -4,7 +4,7 @@ date: 2020-09-25
 authors:
   - frere
 layout: blogpost
-title_image: docker-cover.jpg
+title_image: docker-cover.png
 categories:
   - tutorial
 tags:
@@ -283,11 +283,11 @@ View part three [here]({% post_url 2020/09/2020-09-29-getting-started-with-docke
   <p>
     HIFIS offers free-of-charge workshops and consulting to research groups within the Helmholtz umbrella.
     You can read more about what we offer on our
-    <strong><a href="https://software.hifis.net/services">services page</a></strong>.
+    <strong><a href="{% link services/index.md %}">services page</a></strong>.
     If you work for a Helmholtz-affiliated institution, and think that something like this would be useful to you, send us an e-mail at
     <strong><a href="mailto:{{site.contact_mail}}">{{site.contact_mail}}</a></strong>,
     or fill in our
-    <strong><a href="https://software.hifis.net/services/consulting.html#consultation-request-form">consultation request form</a></strong>.
+    <strong><a href="{% link services/consulting.html %}#consultation-request-form">consultation request form</a></strong>.
   </p>
 </div>
 
diff --git a/_posts/2020/09/2020-09-29-getting-started-with-docker-3.md b/_posts/2020/09/2020-09-29-getting-started-with-docker-3.md
index a072f9f059787391e5927664315e7ebb15860ced..8e8832d1568c68191605f096030c1bd2f7de33ef 100644
--- a/_posts/2020/09/2020-09-29-getting-started-with-docker-3.md
+++ b/_posts/2020/09/2020-09-29-getting-started-with-docker-3.md
@@ -4,7 +4,7 @@ date: 2020-09-29
 authors:
     - frere
 layout: blogpost
-title_image: docker-cover.jpg
+title_image: docker-cover.png
 categories:
     - tutorial
 tags:
@@ -338,11 +338,11 @@ For more details about this, see the "Get In Touch" box below.
   <p>
     HIFIS offers free-of-charge workshops and consulting to research groups within the Helmholtz umbrella.
     You can read more about what we offer on our
-    <strong><a href="https://software.hifis.net/services">services page</a></strong>.
+    <strong><a href="{% link services/index.md %}">services page</a></strong>.
     If you work for a Helmholtz-affilliated institution, and think that something like this would be useful to you, send us an e-mail at
     <strong><a href="mailto:{{site.contact_mail}}">{{site.contact_mail}}</a></strong>,
     or fill in our
-    <strong><a href="https://software.hifis.net/services/consulting.html#consultation-request-form">consultation request form</a></strong>.
+    <strong><a href="{% link services/consulting.html %}#consultation-request-form">consultation request form</a></strong>.
   </p>
 </div>