Log-to-file / logging on Windows with SC.exe

[itdaniher]

Consul Template version

v0.25.1

Expected behavior

Consul-template supports logging to file. Consul-template can be started as a service on Windows, and the resultant messages can be inspected. Consul offers -log-file via stdarg and Nomad offers log_file in the config.

Actual behavior

Consul-template only supports Syslog and stdout/stderr logging mechanisms. Windows discards stdout/stderr messages from services. Seemingly no way to get persistent logging without wrapping consul-template.exe in a script that captures stdout and stderr to a file.

Calling: ArraySeq(sc.exe, create, consul-template, binpath=, C:\opt\consul-template\consul-template.exe)
Calling: ArraySeq(sc.exe, config, consul-template, DisplayName=, Consul-Templat, binPath=, C:\opt\consul-template\consul-template.exe -config=C:\opt\consul-template\config-windows.hcl -vault-token=s.REDACTED -consul-token=REDACTED)
Calling: WrappedArray(sc.exe, start, consul-template)

Steps to reproduce

1. Create and start an instance of consul-template as a service with sc.exe on Windows
2. Attempt to inspect behavior.
3. Unable to inspect behavior - no ability to log messages to a file.

References

Are there any other GitHub issues (open or closed) that should
be linked here? For example:

• Windows SC Service #1382

[eikenb]

They @itdaniher, thanks for taking the time to submit a ticket.

What do applications typically do for logging on Windows? Is it typical to provide something like a '-log-file /path/to/log` style option, either as a command line argument or a config option? What would you like to see?

I'm sure I can look this up but I'm mainly interested in what you want, a real use case. Thanks.

[itdaniher]

I'd love to see -log-file as a command line argument. Consul's semantics here work very nicely for our needs. Not sure what's the norm (fortunately not often problem-solving on Windows!)

Thanks!

[ksandrmatveyev]

Hi @eikenb . I think it will be really useful as we can run consul-template as windows service since 0.26.0 #1382, but we are blind due to no logs we can get. https://www.consul.io/docs/agent/options#_log_file, such as -log-file, -log-rotate-bytes, -log-rotate-duration and -log-rotate-max-files, are what I assume is ok

[deblasis]

Hi there 👋

I just created #1534. It should address this issue by adding -log-file, -log-rotate-bytes, -log-rotate-duration and -log-rotate-max-files and also the corresponding items inside a new configuration stanza named log-file.

I also dared to write the relevant documentation. I hope that's OK.

Cheers!

[mcouillard]

As an alternative, some Windows magic can redirect standard output to a file. So creating the service like this will do it (capturing both standard out, 1, and errors, 2, in the same file).

sc.exe create VaultAgent binPath= "vault.exe agent -config=vault-agent.hcl -log-level=DEBUG 1>> agent.log 2>&1" displayName= "VaultAgent" start= auto