Stack Definition Language (SDL)
Customers / tenants define the deployment services, datacenters, requirements, and pricing parameters, in a "manifest" file (deploy.yaml). The file is written in a declarative language called Software Definition Language (SDL). SDL is a human friendly data standard for declaring deployment attributes. The SDL file is a "form" to request resources from the Network. SDL is compatible with the YAML standard and similar to Docker Compose files.
Configuration files may end in
.yml or .yaml.A complete deployment has the following sections:
Networking - allowing connectivity to and between workloads - can be configured via the Stack Definition Language (SDL) file for a deployment. By default, workloads in a deployment group are isolated - nothing else is allowed to connect to them. This restriction can be relaxed.
Indicates version of Akash configuration file. Currently only
"2.0" is accepted.The top-level
services entry contains a map of workloads to be ran on the Akash deployment. Each key is a service name; values are a map containing the following keys:Name | Required | Meaning |
|---|---|---|
image | Yes | Docker image of the container
Best practices:
|
depends-on | No | NOTE - field is marked for future use and currently has no impact on deployments. |
command | No | Custom command use when executing container |
args | No | Arguments to custom command use when executing the container |
env | No | |
expose | No |
A list of environment variables to expose to the running container.
env:
- API_KEY=0xcafebabe
- CLIENT_ID=0xdeadbeef
- HTTPS is possible in Akash deployments but only self signed certs are generated.
- To implement signed certs the deployment must be front ended via a solution such as Cloudflare. If interested in this path, we have created docs for Cloudflare with Akash.
- You can expose any other port besides 80 as the ingress port (HTTP, HTTPS) port using as: 80 directive if the app understands HTTP / HTTPS. Example of exposing a React web app using this method:
- port: 3000
as: 80
to:
- global: true
accept:
- www.mysite.com
- In the SDL it is only necessary to expose port 80 for web apps. With this specification both ports 80 and 443 are exposed.
expose is a list describing what can connect to the service. Each entry is a map containing one or more of the following fields:Name | Required | Meaning |
|---|---|---|
port | Yes | Container port to expose |
as | No | Port number to expose the container port as |
accept | No | List of hosts to accept connections for |
proto | No | Protocol type. Valid values = tcp or udp |
to | No |
The
as value governs the default proto value as follows:NOTE - when as is not set, it will default to the value set by the port mandatory directive.
NOTE - when one exposes as: 80 (HTTP), the Kubernetes ingress controller makes the application available over HTTPS as well, though with the default self-signed ingress certs.
port | proto default |
80 | http & https |
all others | tcp & udp |
expose.to is a list of clients to accept connections from. Each item is a map with one or more of the following entries:Name | Value | Default | Description |
|---|---|---|---|
service | A service in this deployment | | Allow the given service to connect |
global | true or false | false | If true, allow connections from outside of the datacenter |
If no service is given and
global is true, any client can connect from anywhere (web servers typically want this).If a service name is given and
global is false, only the services in the current datacenter can connect. If a service name is given and global is true, services in other datacenters for this deployment can connect.If
global is false then a service name must be given.profiles.compute is map of named compute profiles. Each profile specifies compute resources to be leased for each service instance uses uses the profile.Example:
This defines a profile named
web having resource requirements of 2 vCPUs, 2 gigabytes of memory, and 5 gigabytes of storage space available.web:
cpu: 2
memory: "2Gi"
storage: "5Gi"
cpu units represent a vCPU share and can be fractional. When no suffix is present the value represents a fraction of a whole CPU share. With a m suffix, the value represnts the number of milli-CPU shares (1/1000 of a CPU share).Example:
Value | CPU-Share |
|---|---|
1 | 1 |
0.5 | 1/2 |
"100m" | 1/10 |
"50m" | 1/20 |
memory, storage units are described in bytes. The following suffixes are allowed for simplification:Suffix | Value |
|---|---|
k | 1000 |
Ki | 1024 |
M | 1000^2 |
Mi | 1024^2 |
G | 1000^3 |
Gi | 1024^3 |
T | 1000^4 |
Ti | 1024^4 |
P | 1000^5 |
Pi | 1024^5 |
E | 1000^6 |
Ei | 1024^6 |
profiles.placement is map of named datacenter profiles. Each profile specifies required datacenter attributes and pricing configuration for each compute profile that will be used within the datacenter. It also specifies optional list of signatures of which tenants expects audit of datacenter attributes.Example:
westcoast:
attributes:
region: us-west
signedBy:
allOf:
- "akash1vz375dkt0c60annyp6mkzeejfq0qpyevhseu05"
anyOf:
- "akash1vl3gun7p8y4ttzajrtyevdy5sa2tjz3a29zuah"
pricing:
web:
denom: uakt
amount: 8
db:
denom: uakt
amount: 100
This defines a profile named
westcoast having required attributes {region="us-west"}, and with a max price for the web and db compute profiles of 8 and 15 uakt per block, respectively. It also requires that the provider's attributes have been signed by the accounts akash1vz375dkt0c60annyp6mkzeejfq0qpyevhseu05 and akash1vl3gun7p8y4ttzajrtyevdy5sa2tjz3a29zuah.Optional
The
signedBy section allows you to state attributes that must be signed by one or more accounts of your choosing. This allows for requiring a third-party certification of any provider that you deploy to.The
deployment section defines how to deploy the services. It is a mapping of service name to deployment configuration.Each service to be deployed has an entry in the
deployment. This entry is maps datacenter profiles to compute profiles to create a final desired configuration for the resources required for the service.Example:
web:
westcoast:
profile: web
count: 20
This says that the 20 instances of the
web service should be deployed to a datacenter matching the westcoast datacenter profile. Each instance will have the resources defined in the web compute profile available to it.GPUs can be added to your workload via inclusion the compute profile section. The placement of the GPU stanza can be viewed in the full compute profile example shown below.
NOTE - currently the only accepted vendor isnvidiabut others will be added soon
profiles:
compute:
obtaingpu:
resources:
cpu:
units: 1.0
memory:
size: 1Gi
gpu:
units: 1
attributes:
vendor:
nvidia:
- model: 4090
storage:
size: 1Gi
To view an example GPU enabled SDL in full for greater context, review this example which utilized the declaration of several GPU models.
The declaration of a GPU model is optional in the SDL. If your deployment does not require a specific GPU model, leave the model declaration blank as seen in the following example.
gpu:
units: 1
attributes:
vendor:
nvidia:
If your deployment is optimized to run on multiple GPU models, include the appropriate list of models as seen in the following example. In this usage, any Akash provider that has a model in the list will bid on the deployment.
gpu:
units: 1
attributes:
vendor:
nvidia:
- model: 4090
- model: t4
Use of Stable Payments is supported in the Akash SDL and is declared in the placement section of the SDL as shown in the example below.
NOTE - currently onlyAxelar USDC (usdc)is supported anddenommust be specified as the precise IBC channel name shown in the example.
placement:
global:
pricing:
web:
denom: ibc/170C677610AC31DF0904FFE09CD3B5C657492170E7E52372E48756B71E56F2F1
amount: 100
bew:
denom: ibc/170C677610AC31DF0904FFE09CD3B5C657492170E7E52372E48756B71E56F2F1
amount: 100
Last modified 1mo ago