How to Use the hypernode-haproxyctl CLI Tool

Hypernode clusters use HAProxy to distribute HTTP requests from the loadbalancer to the application servers. With the hypernode-haproxyctl CLI tool you can inspect and manage the HAProxy service.

Viewing the current status

With the status subcommand, you can see the current status of HAProxy and its backends.

app@abcdef-examplelb-magweb-tbbm ~ $ hypernode-haproxyctl status
HAProxy v2.6.12-1+deb12u3 (released: 2025/10/03, uptime: 98d 22h33m56s)
FRONTEND (OPEN): request rate(160), session rate(7), conn rate(7)
exampleapp1 (UP): request rate(0), session rate(25), conn rate(0)
exampleapp2 (UP): request rate(0), session rate(32), conn rate(0)
exampleapp3 (UP): request rate(0), session rate(28), conn rate(0)
exampleapp4 (UP): request rate(0), session rate(38), conn rate(0)
exampleapp5 (UP): request rate(0), session rate(35), conn rate(0)
BACKEND (UP): request rate(0), session rate(160), conn rate(0)

The output has three sections:

FRONTEND: The internet-facing entry point. Shows how many requests and connections are coming in per second.
exampleapp1-N: Your individual app servers. Common states are UP, DOWN and DRAIN.
BACKEND: The combined pool of all app servers. UP means at least one server is healthy.

If a server shows DOWN unexpectedly, it likely needs attention. DRAIN and MAINTENANCE are usually intentional states used during maintenance.

Managing backends

When troubleshooting or performing maintenance on an app server, you can use the drain subcommand to gracefully remove it from rotation:

app@abcdef-examplelb-magweb-tbbm ~ $ hypernode-haproxyctl drain exampleapp1

The drain command allows existing connections to finish while preventing new traffic from being sent to the server. This is ideal for performing maintenance without disrupting active users.

Once maintenance is complete, you can use the enable subcommand to bring the server back into rotation:

app@abcdef-examplelb-magweb-tbbm ~ $ hypernode-haproxyctl enable exampleapp1