Running multisites Version 1.2.46 (Latest available: 1.2.46) and Patches definition Version 1.2.51 (Latest available: 1.2.51) on Joomla! 1.6.0 Stable [ Onward ] 10-Jan-2011 23:00 GMT. Everything is working with Multisite on the Master. Unix Symbolic Links: Allowed MySQL Version: 5.0.91-log Sharing supported

Check patches installation
Joomla Multi Sites version: 1.2.46 (Latest available: 1.2.45)
Patches definition version: 1.2.52 (Latest available: 1.2.51)
Files Status
ALL OK

Installed another site domain slave1 and it is running on Joomla! 1.6.0 Stable

Separate Database. Writing to database.

However I receive the following error on Master [Manage Sites].

slave id
Warning: mysqli_select_db() [function.mysqli-select-db]: Couldn't fetch mysqli in /homepages/htdocs/dotcom/libraries/joomla/database/database/mysqli.php on line 156

And at the bottom I see: Warning: mysqli_close() [function.mysqli-close]: Couldn't fetch mysqli in /homepages/htdocs/dotcom/libraries/joomla/database/database/mysqli.php on line 117

The slave site is functioning properly so far.

Can you give me more info on the slave site definition that you did to help me reproducing this scenario.

I see that you are using MySQLi
and using Joomla 1.6.0 stable.

I would like be able reproducing it and try discover where the "slave id" is used.
I searched in the sources and didn't find it.
Are you sure it is written "slave id"

It is NOT written "slave id" that was my interpretation of (slave)record 1 field "id" the error is located in the id field.

Warning: mysqli_select_db() [function.mysqli-select-db]: Couldn't fetch mysqli in /homepages/htdocs/dotcom/libraries/joomla/database/database/mysqli.php on line 156

When I click on [ Edit ] site details:

Master site directory: /homepages/htdocs/dotcom

Deployed directory: /homepages/htdocs/slave

Tools are functioning everything is working. Status is confirmed.

I am not completely sure what you mean by slave site definition?

Slave site definition is what is defined in the "manage site" menu when you edit the slave.

So you moreless give me the info.

If I create a slave site with
Site ID = slave
Deploy directory = {root_dir/slave

Do you think that I will be able to reproduce it.
Did you create a fresh slave site and when you get the Joomla Installer selected mysqlI

Did you create a fresh slave site and when you get the Joomla Installer selected mysqlI

Yes I created a fresh slave site. I used an existing DB PHP 5 when installed it and removed all old records. My deploy directory is root_dir/slave. My master dir is root_dir/master. The master is also a fresh install.

Do you think that I will be able to reproduce it.

You should be able to reproduce the error... the only difference: I use 1 and 1 shared hosting using php.ini in each deployed dir.

I just created another slave but this time I installed it in root_dir/master/slave2

It is also showing the same error in the Master (dotcom) [Manage Sites].

Warning: mysqli_select_db() [function.mysqli-select-db]: Couldn't fetch mysqli in /homepages/dotcom/libraries/joomla/database/database/mysqli.php on line 156

But now I am getting an additional error in the first slave record.

Warning: mysqli::ping() [mysqli.ping]: Couldn't fetch mysqli in /homepages/dotcom/libraries/joomla/database/database/mysqli.php on line 139

The slaves and master are all still functioning with no performance issues. All these errors are coming from the Multi Sites Master component only.