[PATCH 35/35] monitor: add option --keep/-K

[Sagi Grimberg]

>>> If it does, it will recreate discovery controllers for every
>>> host_traddr/traddr/trsvcid tuple it finds. "--keep" semantics are
>>> only
>>> necessary for addresses on which no regular (non-discovery)
>>> connection
>>> exists.
>>
>> Wait, Maybe I'm missing something here, but are you saying that for
>> every traddr/trsvcid it finds (both nvm and discovery) it will
>> attempt
>> to connect a discovery controller?
>>
>> If so, this is absolutely wrong.
> 
> Currently, it tries to do that on startup, if (and only if) the
> --startup option is given. My expectation was that the connection
> attempts would simply fail if there was no discovery subsystem to
> connect to. Anyway, it's not the default behavior, and can be dropped
> completely if it's so bad that we shouldn't ever attempt to do it.

IMO it needs to be dropped. I didn't understand this at first because
it never even occurred to me that such an assumption can be even made.

> If the service is started early on during boot, and event-based
> discovery works (i.e. we also have the mDNS part in place), this won't
> be necessary of course.

This isn't necessary regardless. At best the discovery controller
endpoints should be obtained from discovery.conf or equivalent.

I don't even see how does this help in early boot anyways, how
do the existing controllers get connected?