Re: (Isolation Segments) Question about a Cell with mulitiple "placement_tag"s

Sandy Cash Jr <lhcash@...>


My apologies. I initially got the wrong information regarding how Diego
matches placement tags for desiredLRP placement.

It _is_ the case that a cell can only live in one Isolation Segment at a
time, since the matching is not based on simple membership but set
equality. Since the CC only sends a single tag (the name of the
destination IS) in the desiredLRP request, that will only match cells with
that tag and *only that tag*.

So no, there is currently no way for a cell to live in multiple Isolation
Segments in the current release. Eric Malm could weigh in on whether he
sees this behavior changing in the future, since the matching/placement is
all done in the Diego side.



Sandy Cash
Certified Senior IT Architect/Senior SW Engineer
IBM BlueMix
(919) 543-0209

"I skate to where the puck is going to be, not to where it has been.” -
Wayne Gretzky

From: Noburou TANIGUCHI <dev(a)>
To: cf-dev(a)
Date: 03/02/2017 12:41 AM
Subject: [cf-dev] (Isolation Segments) Question about a Cell with
mulitiple "placement_tag"s

Hi team,

Recently I've been trying Isolation Segments for compute tier.

In the official document, it is required to deploy one or more cells with
`diego.rep.placement_tags` to utilize the isolation segment feature.

But I'm wondering why the `diego.rep.placement_tags` is a "single-value
array" [1].

I tried to deploy a cell with two placement tags. The deployment was
successfully finished, but the cell was not recognized as a valid compute

So my questions are:

Q1. Why is the `diego.rep.placement_tags` a "single-value array"?

Q2. A cell with multiple placment tags can be deployed but not recognized
valid. Is this expected behavior for the current implementation?

Q3. Is there any plan to support a cell belonging multiple isolation
segments in the future? If yes, when?


Thanks in advance.

I'm not a ...
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