Logs and exec

Logs and exec

Stream container logs and open interactive shells for user microservices and system microservices. The command is logs (plural).

Node daemon logs and node exec stay on Node logs and exec. This page does not repeat them.

potctl logs microservice myapp/api -n my-ecn
potctl exec microservice myapp/api -n my-ecn

logs and exec.

Running services are also in EdgeOps Console → Workloads, which uses the same WebSocket API.

Names

Pattern	Example	Lookup
User app	myapp/api	User microservice by name.
System app	system-edge01/debug	System microservice when the user application is missing.

Discover names with get microservices and get system-microservices.

Resource	Command
User microservice	describe microservice myapp/api
System microservice	describe system-microservice system-edge01/debug

describe microservice does not describe legacy system-catalog microservices (catalog ids 3 and below). Use describe system-microservice for those.

logs microservice

The command tails stdout and stderr of the workload container on the Edgelet node that hosts the microservice.

Flag	Default	Range
--tail	100	1 to 5000
--follow	true	Stream until you stop it.
--since	unset	RFC3339
--until	unset	RFC3339

1. Resolve the microservice on the user application, then on the system application.
2. The status must be RUNNING. Otherwise the CLI errors.
3. Load the Edgelet node from the namespace and the Controller.
4. On a remote node, open a WebSocket for user or system microservice logs, with the tail options.
5. On a local Edgelet node (kind: LocalAgent), read Docker or Podman logs for the container iofog_<microservice-uuid>. That path dumps the log once. --tail and --follow are not applied on the local engine path.

potctl logs microservice wasm/wasm -n my-ecn
potctl logs microservice system-lima/debug -n my-ecn --follow=false --tail=200

exec microservice

Interactive WebSocket exec into the running workload container. There is no separate attach step. exec agent is the node path and can provision a debug system microservice. That flow is on Node logs and exec.

Requirements:

• The microservice is RUNNING.
• User microservice exec needs a subject with the Developer role.
• System microservices may require SRE. The CLI reports that only SRE can access system microservices.

1. Look up the user microservice. If the application id is invalid, look up the system microservice.
2. Verify RUNNING.
3. Open the user or system exec WebSocket.
4. Attach the local terminal to that session.
5. Closing the session prints a success message.

Up to 3 concurrent exec sessions are allowed per microservice. A fourth session returns HTTP 409.

potctl exec microservice myapp/api -n my-ecn
potctl exec microservice system-edge01/debug -n my-ecn

Protocol limits are on Exec sessions.

Workload commands and node commands

	logs agent	logs microservice
Target	Edgelet daemon on the node	Application or system container
Where	Node logs and exec	This page

	exec agent	exec microservice
Target	Debug system container on the node	The workload container
Provision	May attach a debug microservice	None
Typical role	SRE for node exec	Developer for microservice exec

Rebuild a system microservice

After an image or config change on a Controller-managed system workload:

potctl rebuild system-microservice system-edge01/debug -n my-ecn

User kind: Microservice deploy cannot create system microservices.

Troubleshooting

Message	Likely cause
Microservice is not currently running	Status is not RUNNING. Wait, or fix the deploy.
Insufficient permissions, Developer	The subject needs Developer for user microservice exec.
Only SRE can access system microservices	Use an SRE account, or skip exec on that system microservice.
Maximum of 3 concurrent exec sessions	Close another exec session.
Log session relay unavailable	Controller HA or the NATS relay. Retry.
Timeout waiting for agent connection	The Edgelet node is offline, or the network path is down.

Related

• Microservices
• Microservice fields for status and execStatus on describe
• Node logs and exec
• Exec sessions

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