U/BL - Frequently Asked Questions

Does U/BL use standard LDAP calls for authentication?

The answer to this question depends on the setting used for 'Authenticator' in the U/BL Administrator Options.

If 'Win NT Style' is selected then the 'ADSI WinNT Provider' is used, otherwise U/BL uses the 'ADSI LDAP Provider'.

Is it possible to have more than one U/BL authenticator?

It is only possible to set one domain as the U/BL authenticator. However, in a situation where some U/BL users are in a secondary domain, as long as the domains are in the same forest, they should be able to authenticate each others' accounts.

Please refer to the Microsoft Active Directory documentation for more information.

Is it possible to launch U/BL in U/Gi without a separate login sequence?

You can supply the username and password on the command line in the shortcut that starts U/Gi. This is the only way to run U/BL within U/Gi without the login prompt.

For example:
<UGi path>\uterm.exe -u username -x password <UGi path>\ublnt.ugi

Use STME or $EXECUTE to get a list of files in date order?

The ‘STME 0’ statement can be used to get the next filename (matching a template) from a directory. One big advantage of STME 0 is that the same code works in the same way on all Windows, UNIX and Linux platforms supported by U/BL.

However, the filenames returned aren't in any specific sequence. New files might be returned before older files.

To get files returned in a specific order, one solution is to use $EXECUTE with an operating system command. For example:

On UNIX the operating system command to use is

ls -t -r -1

(-t is time order, -r is reverse the search (oldest first) and -1 is list in one column per line)

However, using this command with $EXECUTE requires use of a variable dimensioned large enough to store the entire result. An alternative would be to write a listing to a temporary file and read that in a line at a time:

00010 DIM CMD$[100],F$[100],X$[100]
00015 LET F$="/tmp/dirlist.",SYS(9)
00020 LET CMD$="ls -t -r -1 > ",F$
00030 REM $EXECUTE CMD$,STAT
00040 IF STAT THEN STOP
00050 OPEN FILE[0,3],F$
00060 DO WHILE NOT EOF(0)
00070 INPUT FILE[0],USING "",X$
00080 PRINT "File: ",X$
00090 END LOOP
00100 CLOSE FILE[0]

How to optimise performance when running on a virtual machine.

The initial configurations to consider are the number of CPUs, disk space & memory allocation allocated when the VM is created.

If the VM server has not been allocated enough memory it will spend time in paging & slow up.

It is usually appropriate to allocate the same amount of memory as if it were a real system so that any page/swap issues are not a limit. This should be worked out from knowing what software is running - e.g SQL Server. Start at 2Gb & work up from there.

Other considerations are the number of VM guest systems running on the host server - does that have enough CPU & memory to cope with all the VMs running?

Note that a program that does a lot of disk I/O could be much more than 5% slower on VM.

Some stats for ideal Virtual PC performance depending on what the program is doing:

CPU: 96-97% of host
Network: 70-90% of host
Disk: 40-70% of host

The following blog post contains some useful tips for optimizing VM performance:

http://www.hanselman.com/blog/VMPerformanceChecklistBeforeYouComplainThatYourVirtualMachineIsSlow.aspx

The Modernization Experts