container stderr: "-slaveLog" is not a valid option

Agent from last Jenkins versions (remoting-4.6.jar) has no -slaveLog parameter, just -agentLog. Parameter name needs to be replaced.

Versions:

• docker-plugin 1.2.1
• jenkins 2.266
• docker engine 19.03.8
• docker-plugin connection to container(s) method: Attach Docker container

Error logs:

WARNING i.j.d.c.DockerMultiplexedInputStream#readInternal: Unexpected data on container stderr: "-slaveLog" is not a valid option
WARNING i.j.d.c.DockerMultiplexedInputStream#readInternal: Unexpected data on container stderr: 
java -jar agent.jar [options...]
WARNING i.j.d.c.DockerMultiplexedInputStream#readInternal: Unexpected data on container stderr:  -agentLog FILE                  : Local agent error log destination (overrides
                                   workDir)
 -auth user:pass                 : If your Jenkins is security-enabled, specify
                                   a valid user name and password
......

[pjdarton]

@Z9n2JktHlZDmlhSvqc9X2MmL3BwQG7tk FYI you can workaround this issue by overriding the default “EntryPoint Cmd” field in the “Connect method” section of the “Docker Agent template”.

The helptext tells you what the default is, and you’ll see the -slaveLog line in there; copy & paste the default into the multi-line text box (expand it first!) and change “slave” to “agent”.

[pjdarton]

You’re missing something - the context that was in my head when I wrote that 😉

My previous comment was referring to the “minimum Jenkins version” that the plugin will work with - i.e. very old versions of Jenkins. I had to bump that from 2.60.3 (which only provided the -slaveLog arg) to 2.73.3 (as that supported both slaveLog and agentLog) in order to enable the plugin to compile & self-test using the “agentLog” argument.

i.e. the plugin code was testing against 2.60.3, and that meant that changing from “slaveLog” to “agentLog” then broke everything as “agentLog” wasn’t supported in 2.60.3. Once I’d switched to testing with 2.73.3 the plugin’s code (which I’d changed to use “agentLog”) started working again.

TL;DR: With this fix, you can’t use Jenkins 2.60.3 anymore, you’ll need to use 2.73.3 or later … and anyone using a recent version of Jenkins will be pleased to find that the plugin’s default is “agentLog” instead of “slaveLog” so it’ll now “just work” again.

…however, as I’ve not done a docker-plugin release since I merged this, you’ll need to use a pre-release build, e.g. from https://repo.jenkins-ci.org/incrementals/io/jenkins/docker/docker-plugin/