Cloud load balancer logs

Last update: April 17 2025

Cloud load balancer logs

For your information

Logging is only available for load balancers in the pool ru-8.

The service is used for logging the load balancer Logging Platform. More details on the principle of operation and the cost of the service in the instructions General information about the Log Platform service.

The following types of events are logged for the load balancer:

• HTTP request;
• TCP connection;
• administrative event — change server status in target group.

Depending on the type of event, a different set is recorded for the event fields.

To collect load balancer logs, you need to enable logging for the balancer. Get the logs can only be done through the API. If you no longer need to collect logs, you can deactivate logging.

Enable logging for the load balancer⁠

You can enable logging through the API or in the control panel — when creating a load balancer or for the existing balancer.

Enable logging for an existing load balancer⁠

Logging uses some of the balancer's computational resources.

Control panel

1. in control panels from the top menu, press Products and select Cloud servers.
2. Go to the section Balancers → tab Balancers.
3. Open the balancer page.
4. In the block Settings in the field Logging click .
5. Check the box Collect technical logs of the balancer.
6. Select a log group or create a new group. Logs from one or more balancers can be recorded in one group.
7. If you have selected a new group, enter its name.
8. Click Save.

OpenStack API

1. Get an IAM token for the project in which the balancer is created.

2. In the query output, copy the value X-Subject-Token.

3. Open the CLI.

4. Enable logging for the balancer:

   curl --location --request PUT 'https://<pool>.cloud.api.selcloud.ru/load-balancer/v2/lbaas/loadbalancers/<loadbalancer_uuid>/log_offloading' \
     --header 'X-Auth-Token: <x_auth_token>' \
     --header 'Content-Type: application/json;charset=utf-8' \
     --data '{
         "log_group": "<log_group_name>"
     }

   Specify:

   • <pool> — pool in which the balancer is created, e.g. ru-8. The address (URL) depends on the region and pool, you can look in the URL list;
   • <loadbalancer_uuid> — Balancer ID. You can view the ID in control panels: from the top menu, press Products → Cloud servers → Balancers → balancer page → under the balancer's name, tap ;
   • <x_auth_token> — The IAM token for the project you copied in step 2;
   • <log_group_name> — name of the log group where the balancer logs will be written. More information about log groups in the subsection Principle of operation instructions General information about the Log Platform service.

Disable logging for the load balancer⁠

Control panel

1. in control panels from the top menu, press Products and select Cloud servers.
2. Go to the section Balancers → tab Balancers.
3. Open the balancer page.
4. In the block Settings in the field Logging click .
5. Uncheck the box Collect technical logs of the balancer.
6. Click Save.

OpenStack API

1. Get an IAM token for the project (X-Auth-Token).

2. In the query output, copy the value X-Subject-Token.

3. Open the CLI.

4. Turn off logging for the balancer:

   curl --location --request DELETE 'https://<pool>.cloud.api.selcloud.ru/load-balancer/v2/lbaas/loadbalancers/<loadbalancer_uuid>/log_offloading' \
     --header 'X-Auth-Token: <x_auth_token>' \
     --header 'Content-Type: application/json;charset=utf-8'

   Specify:

   • <pool> — pool where the balancer is located, e.g. ru-8. The address (URL) depends on the region and pool, you can look in the URL list;
   • <loadbalancer_uuid> — Balancer ID. You can view the ID in control panels: from the top menu, press Products → Cloud servers → Balancers → balancer page → under the balancer's name, tap ;
   • <x_auth_token> — The IAM token for the project you copied in step 2.

Get the logs⁠

Use the instructions Get the logs In the Log Platform section.

Look at the description log fields for the load balancer.

Log fields⁠

Depending on the type of event, the log displays a different set of fields.

HTTP request

loadbalancer_id	Balancer ID
elapsed	Duration of request processing
url	Request URL
version	HTTP protocol version
method	HTTP method of request to the balancer
status	HTTP request response status
bytest_in	Number of bytes transferred in the request
bytes_out	Number of bytes transferred in the response to the request
backend	Balancer target group ID
client	IP address and port from which the request came
frontend	Balancer ID rules
server	Server ID in the balancer's target group
termination_state	Session state at termination, more details in section Session state at disconnection HAProxy documentation
frontend_connections	Number of open connections on the balancer rule
backend_connections	Number of open connections on the balancer's target group
server_connections	Number of open connections on the server where the request was received
retries	Number of repeated request sends to the server
destination	IP address of the server where the request was received
backend_queue	Number of requests on the balancer target waiting to be executed
server_queue	Number of requests on the server waiting for execution

TCP connection

loadbalancer_id
elapsed	Duration of request processing
bytest_in	Number of bytes transferred in the request
bytes_out	Number of bytes transferred in the response to the request
backend	Balancer target group ID
client	Client IP address and port
frontend	Balancer ID rules
server	Server ID in the balancer's target group
termination_state	Session state at termination, more details in section Session state at disconnection HAProxy documentation
frontend_connections	Number of open connections on the balancer rule
backend_connections	Number of open connections on the balancer's target group
server_connections	Number of open connections on the server where the request was received
destination	IP address of the server where the request was received
backend_queue	Number of requests on the target group waiting for fulfillment
server_queue	Number of requests on the server waiting for execution

Administrative event

Administrative event — change server status в target group.

listener_id	Balancer ID rules
loadbalancer_id	Balancer ID
status	New server status in the target group
pool_id	target group ID
member_id	Server ID in the target group