<div class="content" name="R_DhcpV4FailoverAddScopeToRelationship" uuid="861b5d4b-81a1-4013-aaed-92eb2554f437"><p>The <b>R_DhcpV4FailoverAddScopeToRelationship</b> method
adds scopes to an existing failover relationship.</p><dl>
<dd>
<div><pre> DWORD R_DhcpV4FailoverAddScopeToRelationship(
   [in, unique, string] DHCP_SRV_HANDLE ServerIpAddress,
   [in] LPDHCP_FAILOVER_RELATIONSHIP pRelationship
 );
</pre></div>
</dd></dl><p><b>ServerIpAddress: </b>The IP address/host name of
the DHCP server. This parameter is unused.</p><p><b>pRelationship: </b>This is a pointer to a type <b>DHCP_FAILOVER_RELATIONSHIP</b>
structure (section <a href="9153f2b7-e4df-4475-9275-d2092a93bd51" data-linktype="relative-path">2.2.1.2.98</a>)
that contains information about the failover relationship to which scopes as
specified in the <b>pScopes</b> member of the <i>pRelationship</i> parameter
are to be added.</p><p><b>Return Values: </b>A 32-bit unsigned integer value
that indicates return status. A return value of ERROR_SUCCESS (0x00000000)
indicates that the operation was completed successfully. Otherwise, it contains
a Win32 error code, as specified in <a href="../ms-erref/1bc92ddf-b79e-413c-bbaa-99a5281a6c90" data-linktype="relative-path">[MS-ERREF]</a>.
This error code value can correspond to a DHCP-specific failure, which takes a
value between 20000 and 20123, or to any generic failure.</p><dl>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Return value/code</p>
   </th>
   <th>
   <p>Description</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>0x00000000 ERROR_SUCCESS</td>
  <td>The call was successful.</td>
 </tr><tr>
  <td>0x00004E25 ERROR_DHCP_SUBNET_NOT_PRESENT</td>
  <td>IPv4 scope does not exist on the DHCPv4 server.</td>
 </tr><tr>
  <td>0x00004E91 ERROR_DHCP_FO_SCOPE_ALREADY_IN_RELATIONSHIP</td>
  <td>IPv4 scope is already part of another failover relationship.</td>
 </tr><tr>
  <td>0x00004E92 ERROR_DHCP_FO_RELATIONSHIP_DOES_NOT_EXIST</td>
  <td>Failover relationship does not exist.</td>
 </tr><tr>
  <td>0x00004EA5 ERROR_DHCP_FO_SCOPE_SYNC_IN_PROGRESS</td>
  <td>Failover relationship is being re-integrated with the failover partner server.</td>
 </tr><tr>
  <td>0x00004E98 ERROR_DHCP_FO_STATE_NOT_NORMAL</td>
  <td>Failover relationship is not in the NORMAL state.</td>
 </tr></tbody></table>
</dd></dl><p>The opnum field value for this method is 94.</p><p>When processing this call, the DHCP server MUST do the
following:</p><ul><li><p><span><span> 
</span></span>Return ERROR_INVALID_PARAMETER if any of the following are true:</p>
<ul><li><p><span><span>  </span></span>The
<i>pRelationship</i> parameter is NULL.</p>
</li><li><p><span><span>  </span></span>The
<b>relationshipName</b> member of the <i>pRelationship</i> parameter is NULL.</p>
</li><li><p><span><span>  </span></span>The
<b>pScopes</b> member of the <i>pRelationship</i> parameter is NULL.</p>
</li><li><p><span><span>  </span></span>The
<b>NumElements</b> member of the <b>pScopes</b> member of the <i>pRelationship</i>
parameter is 0.</p>
</li></ul></li><li><p><span><span> 
</span></span>Validate whether this method is authorized for read/write access
as specified in section <a href="38840bd0-0a5a-47ed-bc69-0dd870d33aec" data-linktype="relative-path">3.5.5</a>.
If not, return ERROR_ACCESS_DENIED.</p>
</li><li><p><span><span> 
</span></span>Iterate through the <b>DHCPv4ScopesList</b> ADM element on the
DHCPv4 server, and if any of the IPv4 subnet addresses in the <b>pScopes</b>
member of the <i>pRelationship</i> parameter does not have a corresponding <b>DHCPv4ScopesList.DHCPv4Scope</b>
ADM element on the DHCPv4 server, return ERROR_DHCP_SUBNET_NOT_PRESENT.</p>
</li><li><p><span><span> 
</span></span>For any of the IPv4 subnet addresses passed in the <b>pScopes</b>
member of the <i>pRelationship</i> parameter, if the corresponding <b>DHCPv4Scope.DHCPv4IpRange</b>
ADM element is of type DhcpIpRangesBootpOnly enumeration value (section <a href="0a196713-4790-412f-a2d7-893cbad301da" data-linktype="relative-path">2.2.1.2.38</a>), return
ERROR_INVALID_PARAMETER.</p>
</li><li><p><span><span> 
</span></span>If there are no elements in the <b>DHCPv4FailoverRelationshipList</b>
ADM element, return ERROR_FILE_NOT_FOUND; otherwise, iterate through the <b>DHCPv4FailoverRelationshipList</b>
ADM elements, and if any input IPv4 subnet passed in the <b>pScopes</b> member
of the <i>pRelationship</i> parameter is already part of the IPv4 subnets
configured on the <b>DHCPv4FailoverRelationshipList.DHCPv4FailoverRelationship</b>
ADM element, return <b>ERROR_DHCP_FO_SCOPE_ALREADY_IN_RELATIONSHIP</b>.</p>
</li><li><p><span><span> 
</span></span>Iterate through the server ADM element <b>DHCPv4FailoverRelationshipList</b>,
and retrieve the <b>DHCPv4FailoverRelationship</b> ADM element corresponding to
the <b>relationshipName</b> member of the <i>pRelationship</i> parameter. If
the corresponding <b>DHCPv4FailoverRelationship</b> ADM element is not found,
return ERROR_DHCP_FO_RELATIONSHIP_DOES_NOT_EXIST.</p>
</li><li><p><span><span> 
</span></span>If the retrieved <b>DHCPv4FailoverRelationship</b> ADM element&#39;s <b>state</b>
member is not a NORMAL enumeration value, return
ERROR_DHCP_FO_STATE_NOT_NORMAL, or, if the relationship is re-integrating with
the partner server, return ERROR_DHCP_FO_SCOPE_SYNC_IN_PROGRESS. Otherwise, add
the IPv4 subnets passed in the <b>pScopes</b> member of the <i>pRelationship</i>
parameter to the retrieved <b>DHCPv4FailoverRelationship</b> ADM element&#39;s <b>pScope</b>
member.</p>
</li><li><p><span><span> 
</span></span>For each of the input IPv4 subnet addresses passed in the <b>pScopes</b>
member of the <i>pRelationship</i> parameter, iterate through the <b>DHCPv4ScopesList</b>
ADM element and retrieve the corresponding <b>DHCPv4Scope</b> ADM element, and
set the <b>DHCPv4Scope.IsFailover</b> ADM element to TRUE.</p>
</li><li><p><span><span> 
</span></span>Return ERROR_SUCCESS.</p>
</li></ul><p><b>Exceptions Thrown:</b> No exceptions are thrown beyond
those thrown by the underlying RPC protocol <a href="../ms-rpce/290c38b1-92fe-4229-91e6-4fc376610c15" data-linktype="relative-path">[MS-RPCE]</a>.</p></div>