Linux: How to Download, Install, and Start APT

Supported Systems

APT is supported on Redhat Enterprise Linux. APT is currently tested on a 64-bit machine with RHEL 6.7 and the Gnome windowing system. Since the upgrade to Java 7 (starting with APT 21.4) the basic OS requirement is RHEL 5.5 (or better), Ubuntu 12.04 (or better), SuSE 10 SP2 (or better) (and equivalents). APT now includes Java 8, but there is no change to minimum OS.

APT requires a minimum of 512 Megabytes of RAM (memory), but we recommend 1 Gigabyte of RAM. Please see our memory discussion for more information.

APT is available for both 32-bit and 64-bit kernal computers, but the default on the installation page is now 64-bit. (To determine which you have type: "uname -a". If you see "x86_64" you have a 64-bit kernel.)

You will need a PDF reader installed on your machine.

Depending on your institution's computer security measures (firewalls, blocked ports, etc.), you may initially have communication trouble with APT. If you have any concerns please see our firewall webpage.

1. UnInstall the previous version

Note: If you are going to install APT in the same directory as a previous version, please remove the previous version first. But if you are going to install in a separate directory, you would only need to uninstall to save disk space (and possible version confusion).

To get rid of the old version: Delete the entire directory tree where you installed it. (The unix command

rm -rf [directory]

makes this quick because it gets rid of all the subdirectories and does not ask you about overriding permissions.)

2. Download and Install

Choose your operating system: APT is available for both 32-bit and 64-bit kernal computers. (To determine which you have type: "uname -a". If you see "x86_64" you have a 64-bit kernel.)

Proceed to the Installation...

3. Start

Once you have installed APT you invoke it with a script. For instance to start APT type

./APT

in the installation directory. (By default the installation directory is placed in your home directory.) Links are no longer put in your home directory automatically. If you would like to create your own link, here is is the unix command to use in your home directory to create a link named 'apt':

ln -s [your_installation_directory]/APT apt

4. Help

There is a a series of short training movies which will help get you started (there are also web pages with screen shots available on the same page). APT also has documentation available from the "Help" menu (the right most menu on the menu bar).

If you can't find what you need, please contact us at help@stsci.edu.

How to find out about new releases

We maintain a distribution list for announcing new releases of APT. This may be helpful to people who install APT for others to use. Just send a blank email to: APT-users-subscribe-request@maillist.stsci.edu (Unsubscribe by sending a blank email to APT-users-signoff-request@maillist.stsci.edu)

Troubleshooting

If there are problems with the installation you can turn on debug logging and sometimes that will reveal the problem. This debug log would also be useful to send us if you can't figure out the problem. Contact us (through help@stsci.edu) if you have problems with installation. It would also be useful to tell us your exact flavor of linux which you can get from the commands:

uname -a

and

more /etc/issue

To turn debug logging on during installation: Execute these commands in the directory where you downloaded the installer (install-linux-apt.sh):

sh install-linux-apt.sh --keep --noexec
    
cd install-linux-apt

jre/bin/java -DTRACE=true -jar install-linux-apt.jar

To turn debug logging on while running APT: add a command line switch when you invoke APT:

./APT -debug all

Known Installation/Download Problems:

If APT will not do basic GUI functions (like allow you to type in a field)
There are a variety of linux windowing systems and APT is only tested on Gnome. We recently had a user report that they could not type into any field (but they could cut and paste). This turned out to be a problem between Java7 and their windowing system (fvwm2). This particular problem has been fixed by updating the version of Java7 in APT 22.0.2. But if you are having a weird GUI failure, try running Gnome to see if that clears things up and then let us know.
If APT fail with this error
```
Could not create the Java virtual machine.
```
APT may have assigned too large a maximum heap size. Please let us know if this happened. (The work around is to edit the max heap at the bottom of the APT script file. Change the string that looks like:
```
-Xmx5655m
```
to:
```
-Xmx1300m
```
or set it even lower if that is higher than 35% of your RAM).
Check that your machine has current patches
While it is always good to be up to date on patches, we recently had two machines where APT ran very slowly (like 5 minutes to start up!) and it was simply because the machines were behind on patches.
UnsatisfiedLinkError
If you try to install APT and you receive an exception like this:
```
Exception in thread "main" java.lang.UnsatisfiedLinkError:
        /tmp/selfgz1222325908/jre/lib/i386/xawt/libmawt.so:
        libXtst.so.6: cannot open shared object file: No such file or directory 
```
You may have accidentally chosen the 32-bit installer, when in fact you have a 64-bit machine. (There may be a similar message for the converse problem.)
APT window blank
A user running Red Hat Enterprise 5 with Gnome Desktop environment 2.16.0 found that APT came up with a blank screen (save for the Name of the program in the title bar). The problem was resolved by turning off two visual effects (Windows Wobble and Workspaces on Cube).

A user running Ubuntu 9.10 with Gnome Desktop environment also found that APT came up with a blank screen. The problem was resolved by turning off all visual effects (System>Preferences>Appearance>Visual Effect>None).
SELinux issue
One user had trouble installing on Fedora Core 4. The error message in the debug started with:
```
java.lang.UnsatisfiedLinkError
```
He diagnosed the problem as being related to the SELinux feature of FC4. So he simply turned off SELinux (as root) with the command:
```
/usr/sbin/setenforce 0 
```
He said that this command must be rerun each time the computer is restarted. We do not have experience with FC4 or SELinux, so we are not aware of a more elegant solution.
Segmentation fault
If when you bring up the APT program for the first time you may get something like:
```
./APT: line 1: 23262 Segmentation fault
```
The work around may be to edit the script called APT in the installation directory to insert:
```
 ulimit -s 2048 
```
right after the initial:
```
 #!/bin/sh
```
Note that issue will only apply to users that have a ulimit set very low by today's standards.
Installing on a machine with no display
If you are a system manager attempting to install on a server that does not have a display, you will need to use the following commands to install without the interactive pop up windows:
```
sh install-linux-apt.sh --keep --noexec

    cd install-linux-apt

    jre/bin/java -jar install-linux-apt.jar -console
```

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