TrueNAS SCALE Version Documentation
This content follows the TrueNAS SCALE 24.04 (Dragonfish) releases. Use the Product and Version selectors above to view content specific to different TrueNAS software or major version.
Install Custom App Screen
12 minute read.
Application maintenance is independent from TrueNAS SCALE version release cycles. This means app version information, features, configuration options, and installation behavior at the time of access might vary from those in documented tutorials.
In TrueNAS 24.04 (Dragonfish), the Apps feature is provided using Kuberenetes. To propose documentation changes to a Kubernetes-based app available in TrueNAS 24.04 (Dragonfish), click Edit Page in the top right corner.
Future versions of TrueNAS, starting with 24.10 (Electric Eel), provide the Apps feature using Docker. To propose documentation changes for a separately versioned Docker-based app, first use the Product and Version dropdowns to switch to the Nightly version Apps documentation, then click Edit Page.
See Updating Content for more guidance on proposing documentation changes.
The Install Custom App screen allows you to configure third-party applications using settings based on Kubernetes. Use the wizard to configure applications not included in the TRUENAS catalog. The Custom App button on the Discover application screen opens the Install Custom App configuration wizard.
The panel on the right of the screen links to each setting area. Click on a heading or setting to jump to that area of the screen. Click in the Search Input Fields to see a list of setting links.
Settings are grouped into Application Name, Container Images, Container Entrypoint, Container Environment Variables, Networking, Port Forwarding, Storage, Workload Details, Scaling/Upgrade Policy, Resource Reservation, Resource Limits, and Portal Configuration sections.
Application Name has two required settings, Application Name and version. After completing the installation these settings are not editable.
Container Images settings specify the container image details. They define the image, tag, and when TrueNAS pulls the image from the remote repository.
Container Entrypoint settings specify both commands and arguments to use for the image. These can override any existing commands stored in the image. Check the documentation for the application you want to install for entry point commands or arguments you need to enter.
Container Environment Variables settings define additional environment variables for the container. Check the documentation for the image and add any required variables here.
Networking settings specify network policy, addresses, and DNS services if the container needs a custom networking configuration.
See the Kubernetes documentation for more details on host networking. You can create additional network interfaces for the container or give static IP addresses and routes.
By default, containers use the DNS settings from the host system. You can change the DNS policy and define separate nameservers and search domains. See the Kubernetes DNS services documentation for more details.
Settings Information
| Setting | Description |
|---|---|
| Add External Interfaces | Click Add to display the Host Interface and IP Address Management settings. |
| Host Interface | Required. Select a host interface configured on your system from the dropdown list. |
| IPAM Type | Required. Select an IP Address Management option from the dropdown list. Options are Use DHCP or Use Static IP. |
| Static IP Address | Displays when Use Static IP is selected. Click Add to display the Static IP fields to specify the IP address and CIDR value. |
| Static Routes | Displays when Use Static IP is selected. Click Add to the right of Static Routes to add the Destination and Gateway fields. |
| Setting | Description |
|---|---|
| DNS Policy | Select the DNS policy option from the dropdown list. There are four options. See the table in DNS Policy Setting Options below. |
| DNS Configuration | Specify custom DNS configuration to apply to the pod. Configuration fields are Nameservers, Searches, and DNS Options. For more information on Kubernetes DNS configuration see Pod DNS Configuration. |
| Nameservers | Use to add a list of IP addresses to use as DNS servers for the container (pod). Specify at least three nameserver IP addresses. If the DNS policy is set to None the list must contain at least one IP address. If not the DNS policy is set to something other than none, specifying nameservers is optional. Click Add to the right of Nameservers to display a Nameserver entry field. Click again to add another name server. |
| Nameserver | Enter the IP address of the name server. |
| Searches | Optional. Use to add a list of DNS search domains for a host name lookup in the container (pod). The list cannot exceed 32 entries. When specified, the provided list is merged into the base search domain names generated from the chosen DNS policy. Kubernetes allows up to six search domains. Click Add to display a Search Entry field to enter the search value you want to configure. For more information on Kubernetes DNS search configuration see DNS Search Domain List Limits. |
| Search Entry | Enter the search value you want to configure. For example, ns1.svc.cluster-domain.example or my.dns.search.suffix. |
| DNS Options | Optional. Use to add a list of objects where each can have a name and a value property. These merge into the options generated from the specified DNS policy. Click Add to display a block of Option Entry Configuration settings. Click again to display another block of settings. |
| Option Name | Required. Enter the option name. For example, ndots or edns0. |
| Option Value | Required. Enter the value for the option name. For example, 2 for ndots. |
| Provide access to node network namespace for the workload | Select to allow the container to bind to any port. Some ports still require appropriate permissions. Unless needed, we recommend leaving this setting disabled because app containers might try to bind to arbitrary ports like 80 or 443, which the TrueNAS UI already uses. |
For more information on DNS policies see the Kubernetes Pod DNS Policy documentation.
| Option | Description |
|---|---|
| Use Default DNS Policy Where Pod Will Inherit The Name Resolution Configuration From The Node. | This is the Kubernetes default dnsPolicy. With the default behavior, the pod inherits the name resolution configuration from the node that the pods run on. |
| “Kubernetes Internal DNS Will Be Prioritized And Resolved First. If The Domain Does Not Resolve With Internal Kubernetes DNS, The DNS Query Will Be Forwarded To The Upstream Nameserver Inherited From The Node. This Is Useful If The Workload Needs To Access Other Service(S)/Workload(S) Using Kubernetes Internal DNS.” | This is the Kubernetes ClusterFirst dnsPolicy. If no dnsPolicy is specified in Kubernetes, this becomes the default option. |
| For Pods Running With HostNetwork And Wanting To Prioritize Internal Kubernetes DNS Should Make Use Of This Policy. | This is the Kubernetes ClusterFirstWithHostNet dnsPolicy. |
| Ignore DNS Settings From The Kubernetes Cluster | This the the Kubernetes none dnsPolicy. With none, a pod can ignore DNS settings from the Kubernetes environment. |
Port Forwarding settings specify the container ports, node ports, and the transfer protocol. Choose the protocol and enter port numbers for both the container and node. You can define multiple port forwards.
Use port forwarding to reroute container ports that default to the same port number used by another system service or container. See Default Ports for a list of assigned ports in TrueNAS.
The Storage settings specify persistent host paths and share data that separate from the lifecycle of the container. Create the storage volumes in SCALE and set the host path volume to a dataset and directory path. You can mount SCALE storage locations inside the container with host path volumes. Define the path to the system storage and the container internal path for the system storage location to appear. For more details, see the Kubernetes HostPath documentation.
Users can create additional Persistent Volumes (PVs) for storage within the container. PVs consume space from the pool chosen for application management. To do this, name each new dataset and define a path where that dataset appears inside the container.
Settings Information
| Setting | Description |
|---|---|
| Host Path Volumes | Use to configure a persistent host path volume. Click Add to display a block of Host Path Volume settings. |
| Host Path | Required. Enter or click to the left of /mnt to browse to the location of the dataset to populate the Mount Path. Click on the dataset to select and display it in the Mount Path field. |
| Mount Path | Required. Enter the |
| Read Only | Select to make the mount path inside the pod read-only and prevent using the container to store data. Kubernetes recommends scoping it to only require file or directory and mounting it as read only. |
| Setting | Description |
|---|---|
| Memory Backed Volumes | Use to configure a Kubernetes emptydir volume that mounts inside the pod. Click Add to display a block of Memory Backed Volume settings. |
| Mount Path | Required. Enter the path where the Kubernetes emptydir volume mounts inside the pod. |
| Size Limit | Optional. Enter the size of the volume. Use the format, 100Mi, 1Gi, 2Gi, etc. |
| Setting | Description |
|---|---|
| Volumes | Use to configure a persistent volume that mounts inside the pod. Click Add to display a block of Volumes settings. Click again to add another block of settings. |
| Mount Path | Required. Enter the path where the persistent volume mounts inside the pod. |
| Dataset Name | Required. Enter the name of the dataset created for the storage volume. |
Workload Details settings specify how to deploy workloads in the container (pod). Kubernetes defines workloads as applications running in the pod. Workload Details settings specify if containers in a pod run with TTY or STDIN enabled, allow enabling any device on the host or configuring host capabilities, and if you run the container as a user or group.
Scaling/Upgrade Strategy settings configure how application upgrades replace pods.
Select Create new pods and then kill the old ones to recreate the container. This retains the existing configuration and container until the upgrade completes before removing it.
Select Kill existing pods before creating new ones to do rolling upgrades. This removes the existing pod and start with a newly updated pod. Killing existing pods is useful if your old pod is not functioning properly. For fewer issues, select Kill existing pods before creating new ones.
Resource Reservation settings configure GPU device allocation for application processes. Settings only display if the system detects available GPU device(s).
Select the number of devices to allocate from the Select GPU dropdown list of devices. See Allocating GPU for more information.
Resource Limits settings specify the CPU and memory limits to place on the Kubernetes pod.
The Portal Configuration settings configure the web UI portal for the container.
Select Enable WebUI Portal (only supported in TrueNAS SCALE Bluefin) to display the web portal configuration settings.
