show default zone and default group

[HarrisChu]

there are some concerns about default zone.

1. if user upgrade from 2.0.1

   • a storage with partitions should be in a default zone and default group?
   • how about a storage without partitions. e.g. balance remove

2. if user creates space without group.

   • a storage with partitions should be in a default zone and default group?
   • how about a storage without partitions

it's better to show the default zone and default group, and explain the logic how we consider a storage in default zone or not.

[Sophie-Xie]

@critical27 @darionyaphet pls discuss this requirement, is it need be resolved in v2.6.0?

[HarrisChu]

(root@nebula) [nba]> desc space nba;
+----+-------+------------------+----------------+---------+------------+---------------------+-------------+-----------+---------+
| ID | Name  | Partition Number | Replica Factor | Charset | Collate    | Vid Type            | Atomic Edge | Group     | Comment |
+----+-------+------------------+----------------+---------+------------+---------------------+-------------+-----------+---------+
| 1  | "nba" | 100              | 1              | "utf8"  | "utf8_bin" | "FIXED_STRING(128)" | false       | "default" |         |
+----+-------+------------------+----------------+---------+------------+---------------------+-------------+-----------+---------+
Got 1 rows (time spent 945/7564 us)

Tue, 14 Sep 2021 15:03:10 CST

(root@nebula) [nba]> show groups
+------+------+
| Name | Zone |
+------+------+
+------+------+
Empty set (time spent 1253/7305 us)

Tue, 14 Sep 2021 15:05:02 CST

more information

[critical27]

You mean show groups return a default group by default? But I can't figure out how to fill the Zone field...

[HarrisChu]

You mean show groups return a default group by default? But I can't figure out how to fill the Zone field...

Yes, that's also my question... If we figure out the zone with default zone, how we consider which storage belongs to the default zone?

We could have a discussion.

[critical27]

We discuss on a meeting, by default we return: (suppose we have n hosts before)

default group: [all hosts previously, each host is a zone]
zone 1: [old host 1]
...
zone n: [old host n]

WDYT?

[darionyaphet]

You mean show groups return a default group by default? But I can't figure out how to fill the Zone field...

Show default group may be a good idea. I agree with you

[critical27]

Talked offline with @darionyaphet , we'll print default group when exec show groups command, each host will be a separate zone. This is quite reasonable.

But I don't know whether we need to print the host in each default zone(which is the host itself)

[critical27]

Talked offline, will not support this interface until 3.0. Because a host could both belongs to a default zone and a user create zone, which breaks the invariant.

[HarrisChu]

Talked offline, will not support this interface until 3.0. Because a host could both belongs to a default zone and a user create zone, which breaks the invariant.

agree and then close issue