Skip to content

Commit

Permalink
[FAB-8700] Clarify channel update tutorial leader elec
Browse files Browse the repository at this point in the history
The gossip leader election section of the channel update tutorial is
vague about whether any settings need to be changed or what setting
the peers are using for EYFN. This CR clarifies that the settings
are already set for EYFN in the docker-compose file and that the section
is included for reference for adding peers to a network beyond the peer
added by EYFN.

Change-Id: I360849c0d344e8ddbf9cf784cbda37b511591d4a
Signed-off-by: Will Lahti <wtlahti@us.ibm.com>
(cherry picked from commit b1e3e77)
  • Loading branch information
wlahti committed Mar 8, 2018
1 parent 05a71a9 commit fdff463
Showing 1 changed file with 30 additions and 17 deletions.
47 changes: 30 additions & 17 deletions docs/source/channel_update_tutorial.rst
Original file line number Diff line number Diff line change
Expand Up @@ -490,36 +490,49 @@ its contents.
Configuring Leader Election
~~~~~~~~~~~~~~~~~~~~~~~~~~~

Newly joining peers are bootstrapped with the genesis block, which does not contain information about the organization
that is being added in the channel configuration update. Therefore new peers are not able to utilize gossip as
they cannot verify blocks forwarded by other peers from their own organization until they get the configuration
transaction which added the organization to the channel. Newly added peers must therefore have one of the following
.. note:: This section is included as a general reference for understanding
the leader election settings when adding organizations to a network
after the initial channel configuration has completed. This sample
defaults to dynamic leader election, which is set for all peers in the
network in `peer-base.yaml`.

Newly joining peers are bootstrapped with the genesis block, which does not
contain information about the organization that is being added in the channel
configuration update. Therefore new peers are not able to utilize gossip as
they cannot verify blocks forwarded by other peers from their own organization
until they get the configuration transaction which added the organization to the
channel. Newly added peers must therefore have one of the following
configurations so that they receive blocks from the ordering service:

1. Utilize static leader mode and configure the peer to be an organization leader:
1. To utilize static leader mode, configure the peer to be an organization
leader:

::

export CORE_PEER_GOSSIP_USELEADERELECTION=false
export CORE_PEER_GOSSIP_ORGLEADER=true
CORE_PEER_GOSSIP_USELEADERELECTION=false
CORE_PEER_GOSSIP_ORGLEADER=true


.. note:: This configuration must be the same for all new peers added to the channel.
.. note:: This configuration must be the same for all new peers added to the
channel.

2. Utilize dynamic leader election:
2. To utilize dynamic leader election, configure the peer to use leader
election:

::

export CORE_PEER_GOSSIP_USELEADERELECTION=true
export CORE_PEER_GOSSIP_ORGLEADER=false
CORE_PEER_GOSSIP_USELEADERELECTION=true
CORE_PEER_GOSSIP_ORGLEADER=false


.. note:: Because peers of newly added organization won't be able to form membership view, this option will
be similar to the static configuration, as each peer will start proclaiming himself to be a leader.
However eventually once they get updated with the configuration transaction that adds the
organization to the channel, there will be only one active leader for the organization. Therefore it
is recommended to leverage this option if you eventually want the organization's peers to utilize
leader election.
.. note:: Because peers of the newly added organization won't be able to form
membership view, this option will be similar to the static
configuration, as each peer will start proclaiming itself to be a
leader. However, once they get updated with the configuration
transaction that adds the organization to the channel, there will be
only one active leader for the organization. Therefore, it is
recommended to leverage this option if you eventually want the
organization's peers to utilize leader election.


Join Org3 to the Channel
Expand Down

0 comments on commit fdff463

Please sign in to comment.