Skip to content

[6.0] Backport BAG failover fix. Ignore server provided failover partner. #3703

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 10 commits into from
Oct 28, 2025
Merged

[6.0] Backport BAG failover fix. Ignore server provided failover partner. #3703

Show file tree
Hide file tree
Changes from 2 commits
Commits
Show all changes
10 commits
Select commit Hold shift + click to select a range
46a5d0f
Backport fix.
mdaigle Sep 29, 2025
574dcb1
Fix merge conflicts.
mdaigle Oct 20, 2025
66dc42f
Add test case. Doesn't compile.
mdaigle Oct 22, 2025
c85d897
Adjust usage of test servers and app context.
mdaigle Oct 22, 2025
c631c92
Add failover and prelogin count capabilities to test server. Update t…
mdaigle Oct 22, 2025
d3e42d6
Set backing field using reflection.
mdaigle Oct 22, 2025
d895aad
Try clearing pool to make test more reliable.
mdaigle Oct 23, 2025
1310e3d
Use string.Empty
mdaigle Oct 23, 2025
b140339
Review changes
mdaigle Oct 23, 2025
cccd71c
Update app context switch reflection.
mdaigle Oct 23, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion src/Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/SqlCommand.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3611,7 +3611,7 @@ private void CheckNotificationStateAndAutoEnlist()
}

Notification.Options = SqlDependency.GetDefaultComposedOptions(_activeConnection.DataSource,
InternalTdsConnection.ServerProvidedFailOverPartner,
InternalTdsConnection.ServerProvidedFailoverPartner,
identityUserName, _activeConnection.Database);
}

Expand Down
63 changes: 38 additions & 25 deletions ...Microsoft.Data.SqlClient/netcore/src/Microsoft/Data/SqlClient/SqlInternalConnectionTds.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -307,7 +307,6 @@ internal SessionData CurrentSessionData
// FOR CONNECTION RESET MANAGEMENT
private bool _fResetConnection;
private string _originalDatabase;
private string _currentFailoverPartner; // only set by ENV change from server
private string _originalLanguage;
private string _currentLanguage;
private int _currentPacketSize;
Expand Down Expand Up @@ -676,13 +675,7 @@ internal TdsParser Parser
}
}

internal string ServerProvidedFailOverPartner
{
get
{
return _currentFailoverPartner;
}
}
internal string ServerProvidedFailoverPartner { get; set; }

internal SqlConnectionPoolGroupProviderInfo PoolGroupProviderInfo
{
Expand Down Expand Up @@ -1461,7 +1454,7 @@ private void OpenLoginEnlist(TimeoutTimer timeout,
throw SQL.ROR_FailoverNotSupportedConnString();
}

if (ServerProvidedFailOverPartner != null)
if (ServerProvidedFailoverPartner != null)
{
throw SQL.ROR_FailoverNotSupportedServer(this);
}
Expand Down Expand Up @@ -1574,7 +1567,7 @@ private void LoginNoFailover(ServerInfo serverInfo,
newSecurePassword,
connectionOptions.MultiSubnetFailover ? intervalTimer : timeout);

if (connectionOptions.MultiSubnetFailover && ServerProvidedFailOverPartner != null)
if (connectionOptions.MultiSubnetFailover && ServerProvidedFailoverPartner != null)
{
// connection succeeded: trigger exception if server sends failover partner and MultiSubnetFailover is used
throw SQL.MultiSubnetFailoverWithFailoverPartner(serverProvidedFailoverPartner: true, internalConnection: this);
Expand Down Expand Up @@ -1602,7 +1595,7 @@ private void LoginNoFailover(ServerInfo serverInfo,
_currentPacketSize = ConnectionOptions.PacketSize;
_currentLanguage = _originalLanguage = ConnectionOptions.CurrentLanguage;
CurrentDatabase = _originalDatabase = ConnectionOptions.InitialCatalog;
_currentFailoverPartner = null;
ServerProvidedFailoverPartner = null;
_instanceName = string.Empty;

routingAttempts++;
Expand Down Expand Up @@ -1641,7 +1634,7 @@ private void LoginNoFailover(ServerInfo serverInfo,
// We only get here when we failed to connect, but are going to re-try

// Switch to failover logic if the server provided a partner
if (ServerProvidedFailOverPartner != null)
if (ServerProvidedFailoverPartner != null)
{
if (connectionOptions.MultiSubnetFailover)
{
Expand All @@ -1657,7 +1650,7 @@ private void LoginNoFailover(ServerInfo serverInfo,
LoginWithFailover(
true, // start by using failover partner, since we already failed to connect to the primary
serverInfo,
ServerProvidedFailOverPartner,
ServerProvidedFailoverPartner,
newPassword,
newSecurePassword,
redirectedUserInstance,
Expand All @@ -1679,8 +1672,13 @@ private void LoginNoFailover(ServerInfo serverInfo,
{
// We must wait for CompleteLogin to finish for to have the
// env change from the server to know its designated failover
// partner; save this information in _currentFailoverPartner.
PoolGroupProviderInfo.FailoverCheck(false, connectionOptions, ServerProvidedFailOverPartner);
// partner; save this information in ServerProvidedFailoverPartner.

// When ignoring server provided failover partner, we must pass in the original failover partner from the connection string.
// Otherwise the pool group's failover partner designation will be updated to point to the server provided value.
string actualFailoverPartner = LocalAppContextSwitches.IgnoreServerProvidedFailoverPartner ? "" : ServerProvidedFailoverPartner;

PoolGroupProviderInfo.FailoverCheck(false, connectionOptions, actualFailoverPartner);
}
CurrentDataSource = originalServerInfo.UserServerName;
}
Expand Down Expand Up @@ -1741,7 +1739,7 @@ TimeoutTimer timeout
ServerInfo failoverServerInfo = new ServerInfo(connectionOptions, failoverHost, connectionOptions.FailoverPartnerSPN);

ResolveExtendedServerName(primaryServerInfo, !redirectedUserInstance, connectionOptions);
if (ServerProvidedFailOverPartner == null)
if (ServerProvidedFailoverPartner == null)
{
ResolveExtendedServerName(failoverServerInfo, !redirectedUserInstance && failoverHost != primaryServerInfo.UserServerName, connectionOptions);
}
Expand Down Expand Up @@ -1791,12 +1789,21 @@ TimeoutTimer timeout
ServerInfo currentServerInfo;
if (useFailoverHost)
{
// Primary server may give us a different failover partner than the connection string indicates. Update it
if (ServerProvidedFailOverPartner != null && failoverServerInfo.ResolvedServerName != ServerProvidedFailOverPartner)
// Primary server may give us a different failover partner than the connection string indicates.
// Update it only if we are respecting server-provided failover partner values.
if (ServerProvidedFailoverPartner != null && failoverServerInfo.ResolvedServerName != ServerProvidedFailoverPartner)
{
SqlClientEventSource.Log.TryAdvancedTraceEvent("<sc.SqlInternalConnectionTds.LoginWithFailover|ADV> {0}, new failover partner={1}", ObjectID, ServerProvidedFailOverPartner);
failoverServerInfo.SetDerivedNames(string.Empty, ServerProvidedFailOverPartner);
if (LocalAppContextSwitches.IgnoreServerProvidedFailoverPartner)
{
SqlClientEventSource.Log.TryTraceEvent("<sc.SqlInternalConnectionTds.LoginWithFailover|ADV> {0}, Ignoring server provided failover partner '{1}' due to IgnoreServerProvidedFailoverPartner AppContext switch.", ObjectID, ServerProvidedFailoverPartner);
}
else
{
SqlClientEventSource.Log.TryAdvancedTraceEvent("<sc.SqlInternalConnectionTds.LoginWithFailover|ADV> {0}, new failover partner={1}", ObjectID, ServerProvidedFailoverPartner);
failoverServerInfo.SetDerivedNames(string.Empty, ServerProvidedFailoverPartner);
}
}

currentServerInfo = failoverServerInfo;
_timeoutErrorInternal.SetInternalSourceType(SqlConnectionInternalSourceType.Failover);
}
Expand Down Expand Up @@ -1845,7 +1852,7 @@ TimeoutTimer timeout
_currentPacketSize = connectionOptions.PacketSize;
_currentLanguage = _originalLanguage = ConnectionOptions.CurrentLanguage;
CurrentDatabase = _originalDatabase = connectionOptions.InitialCatalog;
_currentFailoverPartner = null;
ServerProvidedFailoverPartner = null;
_instanceName = string.Empty;

AttemptOneLogin(
Expand Down Expand Up @@ -1906,7 +1913,7 @@ TimeoutTimer timeout
_activeDirectoryAuthTimeoutRetryHelper.State = ActiveDirectoryAuthenticationTimeoutRetryState.HasLoggedIn;

// if connected to failover host, but said host doesn't have DbMirroring set up, throw an error
if (useFailoverHost && ServerProvidedFailOverPartner == null)
if (useFailoverHost && ServerProvidedFailoverPartner == null)
{
throw SQL.InvalidPartnerConfiguration(failoverHost, CurrentDatabase);
}
Expand All @@ -1915,8 +1922,13 @@ TimeoutTimer timeout
{
// We must wait for CompleteLogin to finish for to have the
// env change from the server to know its designated failover
// partner; save this information in _currentFailoverPartner.
PoolGroupProviderInfo.FailoverCheck(useFailoverHost, connectionOptions, ServerProvidedFailOverPartner);
// partner.

// When ignoring server provided failover partner, we must pass in the original failover partner from the connection string.
// Otherwise the pool group's failover partner designation will be updated to point to the server provided value.
string actualFailoverPartner = LocalAppContextSwitches.IgnoreServerProvidedFailoverPartner ? failoverHost : ServerProvidedFailoverPartner;

PoolGroupProviderInfo.FailoverCheck(useFailoverHost, connectionOptions, actualFailoverPartner);
}
CurrentDataSource = (useFailoverHost ? failoverHost : primaryServerInfo.UserServerName);
}
Expand Down Expand Up @@ -2138,7 +2150,8 @@ internal void OnEnvChange(SqlEnvChange rec)
{
throw SQL.ROR_FailoverNotSupportedServer(this);
}
_currentFailoverPartner = rec._newValue;

ServerProvidedFailoverPartner = rec._newValue;
break;

case TdsEnums.ENV_PROMOTETRANSACTION:
Expand Down
2 changes: 1 addition & 1 deletion src/Microsoft.Data.SqlClient/netfx/src/Microsoft/Data/SqlClient/SqlCommand.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3899,7 +3899,7 @@ private void CheckNotificationStateAndAutoEnlist()
}

Notification.Options = SqlDependency.GetDefaultComposedOptions(_activeConnection.DataSource,
InternalTdsConnection.ServerProvidedFailOverPartner,
InternalTdsConnection.ServerProvidedFailoverPartner,
identityUserName, _activeConnection.Database);
}

Expand Down
Loading
Loading