<term><literal>START_REPLICATION</literal> <literal>SLOT</literal> <replaceable class="parameter">slot_name</replaceable> <literal>LOGICAL</literal> <replaceable class="parameter">XXX/XXX</replaceable> [ ( <replaceable>option_name</replaceable> [ <replaceable>option_value</replaceable> ] [, ...] ) ]</term>

<listitem>

<para>

Instructs server to start streaming WAL for logical replication, starting

at WAL location <replaceable class="parameter">XXX/XXX</replaceable>. The server can

reply with an error, for example if the requested section of WAL has already

been recycled. On success, server responds with a CopyBothResponse

Instructs server to start streaming WAL for logical replication,

starting at either WAL location <replaceable

class="parameter">XXX/XXX</replaceable> or the slot's

<literal>confirmed_flush_lsn</literal> (see <xref

linkend="view-pg-replication-slots"/>), whichever is greater. This

behavior makes it easier for clients to avoid updating their local LSN

status when there is no data to process. However, starting at a

different LSN than requested might not catch certain kinds of client

errors; so the client may wish to check that

<literal>confirmed_flush_lsn</literal> matches its expectations before

issuing <literal>START_REPLICATION</literal>.

</para>

<para>

The server can reply with an error, for example if the

slot does not exist. On success, server responds with a CopyBothResponse

message, and then starts to stream WAL to the frontend.

</para>

elog(DEBUG1,"cannot stream from%X/%X, minimum is %X/%X, forwarding",

elog(LOG,"%X/%X has been already streamed, forwarding to %X/%X",

LSN_FORMAT_ARGS(start_lsn),

LSN_FORMAT_ARGS(slot->data.confirmed_flush));