Cannot commit transaction (HTTP 400 and "14: err")

[mr-simonski]

I'm using HA-Proxy version 2.2.8-1~bpo10+1 2021/01/14 together with HAProxy Data Plane API v2.2.0 68bd22b on Debian GNU/Linux 10

Currently we have problems committing transactions as the dataplaneapi returns a HTTP 400 and a meaningless error message in the form of 14: err <transaction-id>

This error only occurs on the third commit. All 3 commits are done quickly after each other, maybe 60s pause between them.

When checking the config file created in/tmp/haproxy with /usr/sbin/haproxy -c -V -f /tmp/haproxy/haproxy.cfg.<transaction-id> it seems to be valid.

If I restart Haproxy it immediately works 2 times directly one after the other until it fails again at the third try. It does not help to wait for 5 or 10min, I need to restart Haproxy before it works again.

The dataplaneapi is added as follows:

program api
  command dataplaneapi --host xxx.xxx.xxx.xxx --port 5555 --haproxy-bin /usr/sbin/haproxy --config-file /etc/haproxy/haproxy.cfg --restart-cmd "service haproxy restart" --reload-cmd "service haproxy reload" --reload-delay 5 --userlist dataplane-api --log-to=file --log-file=/tmp/err.log --log-level=trace

The err.log does not contain anything useful to me:

time="2021-02-12T01:42:25+01:00" level=info msg="started handling request" method=PUT remote="yyy.yyy.yyy.yyy:58213" request=/v2/services/haproxy/transactions/825d584e-3661-4085-9a48-42e40e8eaa4f request_id=01EY9V55HHDT6JZ1ZE901VECAPF
time="2021-02-12T01:42:25+01:00" level=info msg="completed handling request" length=85B request_id=01EY9VFF33HF33J27BJPC4JCKK status=400 took=18.818926ms

Any ideas?