Adds upgrading syslog-ng info from the blog

content/headless/axosyslog-intro.md

@@ -1,14 +1,27 @@
 ---
 ---
 {{< include-headless "tagline.md" >}}
-{{< product >}} started as a fork, branched after syslog-ng&trade; v4.7.1 with the following focus:
+{{< product >}} is a drop-in replacement for `syslog-ng`, created by the original creators of `syslog-ng`. (It started as a fork, branched after syslog-ng&trade; v4.7.1).
 
-- Cloud native:
-    - Provides containers, Helm charts, Kubernetes integration, ARM support
-- Parsing and transformation tailored for security data ([FilterX]({{< relref "/filterx/_index.md" >}}), app-parser, app-transform)
-- Performance (eBPF support, alternative memory allocator, and so on),
+## AxoSyslog, the drop-in `syslog-ng` replacement
 
-{{< product >}} (created by the original creators of `syslog-ng`):
+AxoSyslog provides the:
 
-- is a drop in replacement for `syslog-ng`,
-- keeps using the same license and development practices.
+- same binaries (for example, `/usr/sbin/syslog-ng`),
+- same configuration files (`/etc/syslog-ng/syslog-ng.conf`), certificates, etc.,
+- same configuration syntax, and the
+- same license and development practices.
+
+If you’re already using `syslog-ng`, you can [upgrade your existing `syslog-ng` deployments to {{< product >}}]({{< relref "/install/upgrade-syslog-ng/_index.md" >}}) in a matter of minutes.
+
+## More than just a replacement
+
+{{< product >}} also provides:
+
+- detailed metrics about what your pipeline is doing,
+- the [FilterX data processing engine]({{< relref "/filterx/_index.md" >}}),
+- enhanced container and Kubernetes support, including [Helm charts]({{< relref "/install/helm/_index.md" >}}),
+- eBPF integration for efficient kernel-level data collection with minimal overhead,
+- destinations for [ClickHouse]({{< relref "/chapter-destinations/clickhouse/_index.md" >}}), [Microsoft Sentinel, Azure Monitor]({{< relref "/chapter-destinations/azure-monitor/_index.md" >}}), [Google Pub/Sub]({{< relref "/chapter-destinations/google-pubsub-grpc/_index.md" >}}), and many more modern services,
+- [regular releases](https://github.com/axoflow/axosyslog/releases) with new features, and
+- responsive and helpful [community and professional support for {{< product >}} and `syslog-ng`]({{< relref "/support/_index.md" >}}).

content/install/_index.md

@@ -18,10 +18,11 @@ This chapter explains how to install {{% param "product.name" %}} on various pla
 
 - {{% xref "/install/podman-systemd/_index.md" %}}
 - {{% xref "/install/debian-ubuntu/_index.md" %}}
+- {{% xref "/install/rhel-fedora-almalinux/_index.md" %}}
 - {{% xref "/install/docker/_index.md" %}}
 - {{% xref "/install/podman/_index.md" %}}
 - {{% xref "/install/helm/_index.md" %}}
 
-## Other installation methods
+## Upgrade `syslog-ng` to AxoSyslog
 
-{{< include-headless "chunk/rpm-deb-packages.md" >}}
+If you’re already using `syslog-ng`, you can upgrade your existing `syslog-ng` deployments to {{< product >}} in a matter of minutes. For details, see {{% xref "/install/upgrade-syslog-ng/_index.md" %}}.

content/install/upgrade-syslog-ng/_index.md

@@ -0,0 +1,88 @@
+---
+title: Upgrade syslog-ng to AxoSyslog
+linktitle: Upgrade syslog-ng
+weight: 2000
+---
+
+If you’re already using `syslog-ng`, you can upgrade your existing `syslog-ng` deployments to {{< product >}} in a matter of minutes, by simply installing {{< product >}} on the host.
+
+We assume that you’ve installed `syslog-ng` from the repositories of your distribution. To upgrade to {{< product >}}, complete the following steps.
+
+1. Check that the syslog-ng service is running:
+
+    ```shell
+    sudo systemctl syslog-ng status
+    ```
+
+    The output will look something like:
+
+    ```shell
+    syslog-ng.service - System Logger Daemon
+     Loaded: loaded (/usr/lib/systemd/system/syslog-ng.service; enabled; preset>
+     Active: active (running) since Thu 2025-02-27 17:04:28 CET; 11s ago
+       Docs: man:syslog-ng(8)
+   Main PID: 254 (syslog-ng)
+      Tasks: 2 (limit: 9594)
+     Memory: 19.6M (peak: 20.8M)
+        CPU: 215ms
+     CGroup: /system.slice/syslog-ng.service
+             └─254 "[rosetta]" /usr/sbin/syslog-ng /usr/sbin/syslog-ng -F
+    ```
+
+1. Check the version of `syslog-ng` you have by running:
+
+    ```shell
+    syslog-ng --version
+    ```
+
+    The output will start with something like:
+
+    ```shell
+    syslog-ng 4 (4.8.1)
+    Config version: 4.2
+    Installer-Version: 4.8.1
+    ```
+
+1. Add the {{< product >}} repository for your distribution and install {{< product >}}. For details, see the installation sections:
+
+    - {{% xref "/install/debian-ubuntu/_index.md" %}}
+    - {{% xref "/install/rhel-fedora-almalinux/_index.md" %}}
+
+    The installation replaces the `syslog-ng` packages with {{< product >}} packages, but provides the same binaries (for example, `/usr/sbin/syslog-ng`). It will keep using the existing configuration files (`/etc/syslog-ng/syslog-ng.conf`), certificates, and so on.
+
+1. Check that the `syslog-ng` service is still running:
+
+    ```shell
+    sudo systemctl syslog-ng status
+    ```
+
+    The output should be identical to the earlier result:
+
+    ```shell
+    syslog-ng.service - System Logger Daemon
+     Loaded: loaded (/usr/lib/systemd/system/syslog-ng.service; enabled; preset>
+     Active: active (running) since Thu 2025-02-27 17:07:41 CET; 42s ago
+       Docs: man:syslog-ng(8)
+   Main PID: 1936 (syslog-ng)
+      Tasks: 2 (limit: 9594)
+     Memory: 79.9M (peak: 83.1M)
+        CPU: 462ms
+     CGroup: /system.slice/syslog-ng.service
+             └─1936 "[rosetta]" /usr/sbin/syslog-ng /usr/sbin/syslog-ng -F
+    ```
+
+1. Check the version of `syslog-ng` you have by running:
+
+    ```shell
+    syslog-ng --version
+    ```
+
+    You’ll see that now you’re running {{< product >}}:
+
+    ```shell
+    axosyslog 4 (4.10.1)
+    Config version: 4.2
+    Installer-Version: 4.10.1
+    ```
+
+In case you run into any issues, [contact us]({{< relref "/support/_index.md" >}}).