Why the vlan cli always add member port to cfg_db VLAN table field 'members'?

[dawnbeauty]

• VLAN Schema

members of VLAN table -- https://github.com/Azure/SONiC/wiki/Configuration
What's the mean of field 'members' of VLAN table?
According to the code logic of vlanmgr, it only process the items in members@, but not members. And it treat all items in members@ as untagged members. The comment explain that This is to be compatible with access VLAN configuration from minigraph. So, can we ignore this field if we use config_db.json instead of minigraph?

• VLAN CLI
  config vlan member add always add member port to the filed 'members' of VLAN table, regardless of tagged or untagged member. But, as previous section, we known that the members field is only used for untagged member.

It seems to be a bug and should clarify the role of members(or members@)

[guxianghong]

I should be a bug. In Table::get( ), @ in member@ have been stripped.

bool Table::get(const string &key, vector &values)
{
RedisCommand hgetall_key;
hgetall_key.format("HGETALL %s", getKeyName(key).c_str());
RedisReply r = m_pipe->push(hgetall_key, REDIS_REPLY_ARRAY);
redisReply *reply = r.getContext();
values.clear();

if (!reply->elements)
    return false;

if (reply->elements & 1)
    throw system_error(make_error_code(errc::address_not_available),
                       "Unable to connect netlink socket");

for (unsigned int i = 0; i < reply->elements; i += 2)
{
    values.emplace_back(stripSpecialSym(reply->element[i]->str),
                                reply->element[i + 1]->str);
}

return true;

}

[jipanyang]

The "members@" field in vlan configDB table is for backward compatibility. If you use configb.json directly, VLAN_MEMBER_TABLE would be a better choice for vlan member configuration: https://github.com/Azure/sonic-swss/blob/master/doc/swss-schema.md#vlan_member_table

[guxianghong]

Thanks for clarification. JSON configuration example is from the page, it's better to remove the vlan member configuration for this page: https://github.com/Azure/SONiC/wiki/Configuration:
"VLAN": {
"Vlan1000": {
"dhcp_servers": [
"192.0.0.1",
"192.0.0.2",
"192.0.0.3",
"192.0.0.4"
],
"members": [
"Ethernet0",
"Ethernet4",
"Ethernet8",
"Ethernet12"
],
"vlanid": "1000"
}
},

[dawnbeauty]

@jipanyang thanks. And what do you think about the behavior of cli config vlan member add? The cli add ports not only VLAN_MEMBER_TABLE but also VLAN_TABLE|members. The port will be automatically set to be an untagged member even if we just want to add a tagged member.
Seems to me, it's a bug.
https://github.com/Azure/sonic-utilities/blob/8b6aea19ce048741b49fcc48979730b086ac62ea/config/main.py#L702

[jipanyang]

VLAN_TABLE|members

If "config vlan member add" adds VLAN_TABLE|members unconditionally, I agree with you that is a bug. Would you provide a fix to the problem? thanks!

[dawnbeauty]

Sure, later will link to the PR.

[dawnbeauty]

@jipanyang please help to review(sonic-net/sonic-utilities#768)