Many motherboards nowadays have integrated gigabit ethernet that use the Realtek NIC chipset.

The Realtek r8168B network card does not work out of the box in Redhat/Centos 5.3: instead of loading the r8168 driver, modprobe loads the r8169 driver, which is broken as can be seen with ifconfig which shows large amounts of dropped packets. A solution is to download the r8168 driver from the Realtek website and install it using the following steps:

Check whether the built-in driver, r8169.ko (or r8169.o for kernel 2.4.x), is installed.

# lsmod | grep r8169

If it is installed remove it.

# rmmod r8169

Download the R8168B linux driver from here into /root.

Unpack the tarball :

# cd /root
# tar vjxf r8168-8.012.00.tar.bz2

Change to the directory:

# cd r8168-8.012.00

If you are running the target kernel, then you should be able to do :

# make clean modules   
# make install
# depmod -a
# insmod ./src/r8168.ko (or r8168.o in linux kernel 2.4.x)

make sure modprobe knows not to use r8169, and that depmod doesn’t find the r8169 module.

# echo "blacklist r8169" >> /etc/modprobe.d/blacklist
# mv /lib/modules/`uname -r`/kernel/drivers/net/r8169.ko   \
        /lib/modules/`uname -r`/kernel/drivers/net/r8169.ko.bak

You can check whether the driver is loaded by using the following commands.

# lsmod | grep r8168
# ifconfig -a

If there is a device name, ethX, shown on the monitor, the linux driver is loaded. Then, you can use the following command to activate it.

# ifconfig ethX up

After this you should not see any more dropped packets reported.

In this article Barry Mavin, CEO and Chief Software Architect for Recital, gives details on Working with user-defined Functions in the Recital Database Server.

Overview

User-defined functions (UDFs) are collections of statements written in the Recital 4GL (compatible with Visual FoxPro) stored under a name and saved in a Database. User-defined functions are just-in-time compiled by the Recital database engine. User-defined functions can be used in SQL statements to extend the power and flexibility of the inbuilt functions. Using the Database Administrator in Recital Enterprise Studio, you can easily create, view, modify, and test Stored Procedures, Triggers, and user-defined functions.

Tip

Creating and Editing user-defined functions

To create a new User-defined function,  right-click the Procedures node in the Databases tree of the Project Explorer and choose Create. To modify an existing User-defined function select the User-defined function in the Databases Tree in the Project Explorer by double-clicking on it or selecting Modify from the context menu. By convertion we recommend that you name your User-defined functions beginning with "f_xxx_", where xxx is the name of the table that they are associated with.

Testing the user-defined function

To test run the user-defined function, select it in the Databases Tree in the Project Explorer by double-clicking on it. Once the Database Administrator is displayed, click the Run button to run it.

Example

Example: user-defined function "f_order_details_total".

////////////////////////////////////////////////////////////////////////
// example user-defined function
function f_order_details_total(pUnitprice, pQuantity, pDiscount)
    return (pUnitprice + pQuantity + pDiscount) > 0
endfunc

Example: using the user-defined function in a SQL SELECT statement.

////////////////////////////////////////////////////////////////////////
// sample code to use a user-defined function in a SQL SELECT statement
select * from customers where f_order_details_total(Unitprice, Quantity, Discount)

Using user-defined function libraries with the Recital Database Server

You can place all of the user-defined functions associated with a particular table into a procedure library. You then define an Open Trigger for the table that opens up the procedure library whenever the table is accessed. This is a much faster way of using user-defined functions as it reduces the amount of file open/close operations during a query and also simplifies development and maintenance.

By convertion we recommend that you should name the library using the convention "lib_xxx", where xxx is the name of the table that the library is associated with.

Example: procedure library in lib_order_details.

////////////////////////////////////////////////////////////////////////
// example user-defined functions
function f_order_details_total(pUnitprice, pQuantity, pDiscount)
    return (pUnitprice * pQuantity - pDiscount) > 0
endfunc

function f_order_details_diff(pUnitprice, pQuantity, pDiscount, pValue)
    return f_order_details_total(pUnitprice, pQuantity, pDiscount) - pValue
endfunc

Example: Open Trigger in dt_order_details_open.

////////////////////////////////////////////////////////////////////////
// This trigger will open up the procedure library when the table is opened
set procedure to lib_order_details additive

Example: Close Trigger in dt_order_details_close.

////////////////////////////////////////////////////////////////////////
// This trigger will close the procedure library when the table is closed
close procedure lib_order_details

Example: using the user-defined function in a SQL SELECT statement.

////////////////////////////////////////////////////////////////////////
// sample code to use a user-defined function in a SQL SELECT statement
select * from customers where f_order_details_total(Unitprice, Quantity, Discount)

User-defined functions can also be used with any of the Client Drivers that work with the Recital Database Server.

This guide will assist you in setting up an rsnapshot backup server on your network. rsnapshot uses rsync via ssh to perform unattended backups of multiple systems in your network. The guide can be found on the centos website here.

When installing nomachine on redhat 5.3 64-bit be sure to: