kbase: debuglogs: Add a 'TL; DR' section for enabling logging in most common case

[PATCH] kbase: debuglogs: Add a 'TL; DR' section for enabling logging in most common case

Posted by Peter Krempa 1 year, 1 month ago

The document grew a bit too much explaining all the mistakes we've seen
the users do when configuring logging. Add a section distilling the
configuration of the most basic scenario which we can refer to when
upstream issues are reported. The scenario is for a runtime setting of
logging into a file applied to the 'virtqemud' daemon.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
---
 docs/kbase/debuglogs.rst | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/docs/kbase/debuglogs.rst b/docs/kbase/debuglogs.rst
index 53d70ee748..811ccf0102 100644
--- a/docs/kbase/debuglogs.rst
+++ b/docs/kbase/debuglogs.rst
@@ -16,6 +16,22 @@ server side that matters as nearly all interesting work takes place there.
 Moreover, libvirt catches stderr of all running domains. These can be useful as
 well.

+TL;DR - Enable debug logs for most common scenario
+===================================================
+
+This applies to the most common scenario of ``system`` instance of
+``virtqemud``. Log setting is not persisted, so a restart of ``virtqemud`` or
+the system clears this setting::
+
+   # virt-admin -c virtqemud:///system daemon-log-outputs "3:journald 1:file:/var/log/libvirt/libvirtd.log"
+   # virt-admin -c virtqemud:///system daemon-log-filters "3:remote 4:event 3:util.json 3:util.object 3:util.dbus 3:util.netlink 3:node_device 3:rpc 3:access 1:*"
+
+   # # optionally disable timeout of the daemon
+   # virt-admin -c virtqemud:///system daemon-timeout 0
+
+For any other configuration please read the rest of the document. If you want
+to persist the log level and log outputs settings edit
+``/etc/libvirt/virtqemud.conf`` and look for ``log-filters`` and ``log-outputs``

 Logging settings in libvirt
 ===========================
-- 
2.39.2

Re: [PATCH] kbase: debuglogs: Add a 'TL; DR' section for enabling logging in most common case

Posted by Daniel P. Berrangé 1 year, 1 month ago

On Mon, Apr 17, 2023 at 01:38:31PM +0200, Peter Krempa wrote:
> The document grew a bit too much explaining all the mistakes we've seen
> the users do when configuring logging. Add a section distilling the
> configuration of the most basic scenario which we can refer to when
> upstream issues are reported. The scenario is for a runtime setting of
> logging into a file applied to the 'virtqemud' daemon.
> 
> Signed-off-by: Peter Krempa <pkrempa@redhat.com>
> ---
>  docs/kbase/debuglogs.rst | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/docs/kbase/debuglogs.rst b/docs/kbase/debuglogs.rst
> index 53d70ee748..811ccf0102 100644
> --- a/docs/kbase/debuglogs.rst
> +++ b/docs/kbase/debuglogs.rst
> @@ -16,6 +16,22 @@ server side that matters as nearly all interesting work takes place there.
>  Moreover, libvirt catches stderr of all running domains. These can be useful as
>  well.
> 
> +TL;DR - Enable debug logs for most common scenario
> +===================================================
> +
> +This applies to the most common scenario of ``system`` instance of
> +``virtqemud``. Log setting is not persisted, so a restart of ``virtqemud`` or
> +the system clears this setting::
> +
> +   # virt-admin -c virtqemud:///system daemon-log-outputs "3:journald 1:file:/var/log/libvirt/libvirtd.log"
> +   # virt-admin -c virtqemud:///system daemon-log-filters "3:remote 4:event 3:util.json 3:util.object 3:util.dbus 3:util.netlink 3:node_device 3:rpc 3:access 1:*"
> +
> +   # # optionally disable timeout of the daemon
> +   # virt-admin -c virtqemud:///system daemon-timeout 0

Given that we have --timeout present by default, I'd say we should make
this a stronger recommendation, or at least mention why you would really
really really want to use this most of the time.

> +
> +For any other configuration please read the rest of the document. If you want
> +to persist the log level and log outputs settings edit
> +``/etc/libvirt/virtqemud.conf`` and look for ``log-filters`` and ``log-outputs``
> 
>  Logging settings in libvirt
>  ===========================
> -- 
> 2.39.2
> 

With regards,
Daniel
-- 
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Re: [PATCH] kbase: debuglogs: Add a 'TL; DR' section for enabling logging in most common case

Posted by Peter Krempa 1 year, 1 month ago

On Mon, Apr 17, 2023 at 16:15:29 +0100, Daniel P. Berrangé wrote:
> On Mon, Apr 17, 2023 at 01:38:31PM +0200, Peter Krempa wrote:
> > The document grew a bit too much explaining all the mistakes we've seen
> > the users do when configuring logging. Add a section distilling the
> > configuration of the most basic scenario which we can refer to when
> > upstream issues are reported. The scenario is for a runtime setting of
> > logging into a file applied to the 'virtqemud' daemon.
> > 
> > Signed-off-by: Peter Krempa <pkrempa@redhat.com>
> > ---
> >  docs/kbase/debuglogs.rst | 16 ++++++++++++++++
> >  1 file changed, 16 insertions(+)
> > 
> > diff --git a/docs/kbase/debuglogs.rst b/docs/kbase/debuglogs.rst
> > index 53d70ee748..811ccf0102 100644
> > --- a/docs/kbase/debuglogs.rst
> > +++ b/docs/kbase/debuglogs.rst
> > @@ -16,6 +16,22 @@ server side that matters as nearly all interesting work takes place there.
> >  Moreover, libvirt catches stderr of all running domains. These can be useful as
> >  well.
> > 
> > +TL;DR - Enable debug logs for most common scenario
> > +===================================================
> > +
> > +This applies to the most common scenario of ``system`` instance of
> > +``virtqemud``. Log setting is not persisted, so a restart of ``virtqemud`` or
> > +the system clears this setting::
> > +
> > +   # virt-admin -c virtqemud:///system daemon-log-outputs "3:journald 1:file:/var/log/libvirt/libvirtd.log"
> > +   # virt-admin -c virtqemud:///system daemon-log-filters "3:remote 4:event 3:util.json 3:util.object 3:util.dbus 3:util.netlink 3:node_device 3:rpc 3:access 1:*"
> > +
> > +   # # optionally disable timeout of the daemon
> > +   # virt-admin -c virtqemud:///system daemon-timeout 0
> 
> Given that we have --timeout present by default, I'd say we should make
> this a stronger recommendation, or at least mention why you would really
> really really want to use this most of the time.

I went with 'optionally' just because the admin API that does this is
relatively recent.

I can try to come up with a stronger suggestion by adding the version
when it became available.

Re: [PATCH] kbase: debuglogs: Add a 'TL; DR' section for enabling logging in most common case

Posted by Michal Prívozník 1 year, 1 month ago

On 4/17/23 13:38, Peter Krempa wrote:
> The document grew a bit too much explaining all the mistakes we've seen
> the users do when configuring logging. Add a section distilling the
> configuration of the most basic scenario which we can refer to when
> upstream issues are reported. The scenario is for a runtime setting of
> logging into a file applied to the 'virtqemud' daemon.
> 
> Signed-off-by: Peter Krempa <pkrempa@redhat.com>
> ---
>  docs/kbase/debuglogs.rst | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

Michal