D Oracle Exadata System Software Accessibility Recommendations

Use these tips for using screen readers and screen magnifiers with Oracle Exadata System Software utilities.

Oracle Exadata System Software includes tools such as dcli and cellcli that you can run from the command line.

• Tips on Using Screen Readers and Braille Displays
  Use the following tips when using screen readers with Oracle Exadata System Software
• Tips on Using Screen Magnifiers
  Use the following tips when using screen magnifiers with Oracle Exadata System Software
• Tips on Using Exawatcher Charts
  Exawatcher is an Exadata specific tool that collects performance data from Exadata storage cells.
• Oracle Exadata Deployment Assistant (OEDA) Web interface Accessibility
  The OEDA Web interface conforms with the Web Content Accessibility Guidelines version 2.0 at the AA level (WCAG 2.0 AA).

D.1 Tips on Using Screen Readers and Braille Displays

Use the following tips when using screen readers with Oracle Exadata System Software

Examples of screen readers include JAWS, SuperNova, and NVDA. Each of these provides text-to-speech output and supports braille displays.

• Use a character mode based terminal such as Putty or Cygwin. Do not use an X-Windows-based VNC.

• For screen reader users, we recommend installing "screen" in order to get multiple session support. The Linux based screen program allows for multiple sessions in different windows. You can access each session with keyboard based commands, for example, Ctrl-a. Screen allows you to detach or re-attach to a given window session. Like VNC, if you get disconnected when running Oracle ExaCHK, or patchmgr, or other program, you can re-attach to and resume that session.

  The screen package is not installed by default on Exadata. You will need to install it using yum. See the "How To Use Linux Screen" tutorial at https://www.rackaid.com/blog/linux-screen-tutorial-and-how-to/ for details.

• In the settings of the terminal software, set the cursor type to "block" cursor, not blinking or flashing.

• The output of the commands can generate a significant amount of information and might spill off the terminal window, and the virtual window or braille display. For example, the following command can generate a long alert history output:

  dcli -g cell_group -l root cellcli list alerthistory
  

  To display the output one screen-full at a time, pipe the output through the more command, as in the following:

  dcli -g cell_group -l root cellcli list alerthistory | more
  

  You can then use the space bar key to page through the output.

• When exachk or dbnodeupdate.sh is launched interactively, do not pipe its output to the more or page commands. As it runs, it displays informational messages on the terminal. The messages pause when exachk requires user input, then resume after input is received. Important messages, user input, errors, and check results are logged in various files. The results from exachk are written to an HTML report. All you need to do is to transfer the HTML report to a computer that runs your assistive technology and open the HTML report in a browser that you can access with your assistive technology.

• If you are running the patchmgr utility, and it is performing a task that takes some time to complete, the output displays a "spinner" and a countdown clock. The "spinner" cycles through the \, |, and / characters in-place, and the countdown clock is updated periodically. When the task is done, the output displays a "success" or "error" message, depending on the outcome. The output messages are also logged in a log file.

• A few recommended screen reader settings include the following (JAWS is used here just as an example):

  • Set the JAWS cursor to "All". Use the key combination of Insert + s until you hear "All".

  • You may need to turn off virtual cursor. If you are using JAWS, you can do this using the key combination of Insert + z.

  • Use the virtual window to capture text. If you are using JAWS, you can do this using the key combination of Insert + Alt + w.

D.2 Tips on Using Screen Magnifiers

Use the following tips when using screen magnifiers with Oracle Exadata System Software

Examples of screen magnifiers include ZoomText, MAGic, and SuperNova.

• Screen magnifiers can support both character-based terminals and X-Window-based VNC.

• If you are using the screen reader function of the screen magnifier (ZoomText screen reader), then you should use a character-based terminal as described above.

• If you are using a VNC, decide your preference for a window display, for example, TWM or ICE. A display setting for ICE can be done with the following:

  vncserver -geometry 1600x950 :2
  

  1600x950 specifies the display size, and :2 specifies the VNC display number.

D.3 Tips on Using Exawatcher Charts

Exawatcher is an Exadata specific tool that collects performance data from Exadata storage cells.

The data collected by Exawatcher can be graphed and presented in web pages. The web pages are based on Oracle JavaScript Extension Toolkit (JET), HTML and some use of ARIA. The Exawatcher pages can present charts which can be navigated using only a keyboard.

D.4 Oracle Exadata Deployment Assistant (OEDA) Web interface Accessibility

The OEDA Web interface conforms with the Web Content Accessibility Guidelines version 2.0 at the AA level (WCAG 2.0 AA).

The OEDA Web interface was built using Oracle JET, which provides support for:

• Keyboard and touch navigation

  Oracle JET components follow the Web Accessibility Initiative - Accessible Rich Internet Application (WAI-ARIA) guidelines. You can find the Oracle JET hotkey information at Oracle JavaScript Extension Toolkit (JET) Keyboard and Touch Reference.

• Zoom

  Oracle JET supports browser zooming up to 200%. For example, on the Firefox browser, you can choose View, then Zoom, and then Zoom In.

• Screen reader

  Oracle JET supports screen readers such as JAWS, Apple VoiceOver, and Google Talkbalk by generating content that complies with WAI-ARIA standards, and no special mode is needed.

• Oracle JET component roles and names

  Each component has an appropriate role, such as button, link, and so on, and each component supports an associated name (label), if applicable.

• Sufficient color contrast

  Oracle JET provides the Alta theme which is designed to provide a luminosity contrast ratio of at least 4.5:1.

OEDA Web Interface Overview

The OEDA Web interface contains two regions. The navigation region occupies the leftmost portion of the page, and the main region occupies the rest. The navigation region contains a list of sections while the main region contains various fields and other elements that are used to specify various configuration details and control the user interface.

The major sections are:

• Select Hardware
• Choose Operating System
• RAC Networks
• Users and Groups
• Define Clusters
• Diskgroups
• Create Database Homes
• Create Database
• Cluster Networks
• Alerting
• Comments

Initially, the Select Hardware section is the only active section. As each section is completed, the next section becomes active in the navigation region and corresponding details are added to the main region. Sections are generally completed in order, but the interface allows users to navigate back to previous sections and make changes. Elements relating to each section are grouped in collapsible areas and each area contains buttons to expand and collapse the area.

OEDA-Specific Keyboard Shortcuts

The following table lists keyboard shortcuts for controlling and navigating around the OEDA Web interface.

Description	Windows	Mac OS
Collapse all sections	Alt+Ctrl+C	Option+Ctrl+C
Expand all sections	Alt+Ctrl+E	Option+Ctrl+E
Move focus to the Options menu	Alt+Ctrl+M	Option+Ctrl+M
Move focus to the main region	Alt+Ctrl+N	Option+Ctrl+N

Keyboard and Screen Reader Navigation using OEDA

When you start the OEDA Web interface, the focus is initially placed on the Options menu button. Activating the Options menu button opens the menu and displays the list of menu items. When the focus is on the Options menu button, pressing the Tab key moves the focus to the navigation region. When the focus is on the navigation region, pressing the Tab key moves the focus to the main region.

To access the Options menu from anywhere, use the keyboard shortcut (Alt+Ctrl+M on Windows or Option+Ctrl+M on Mac OS). To return the focus back to the main region, use Alt+Ctrl+N on Windows or Option+Ctrl+N on Mac OS.

OEDA uses a tabbed interface to represent multiple instances in a section. For example, the Select Hardware section contains the "+" button, which creates a new tab that contains the details for another rack. When a new tab is created, the focus moves to the new tab. You can navigate across multiple tabs by using the arrow keys and you can activate the tab by using the space bar or Enter key. When the focus is on a tab, the JAWS screen reader identifies the tab label and whether it is removable.

Selecting an active section in the navigation region does not move focus to the associated area in the main region. This is a known issue, which is tracked using bug 35029653. To work around the issue using only the keyboard, do the following:

1. Use the keyboard shortcut to collapse all sections in the main region (Alt+Ctrl+C on Windows or Option+Ctrl+C on Mac OS).

2. Use the Tab key to navigate to the main region.

3. In the main region, use the Tab key (or Shift+Tab) to move to the desired section in the list of collapsed sections.

4. Activate and expand the desired section by using the space bar or Enter key.

To work around the issue using the JAWS screen reader:

1. Use the JAWS keyboard shortcut to get a list of active buttons (Ctrl+Insert+B).

2. Use the JAWS button list dialog to navigate to the expand/collapse button associated with the desired section.

When using JAWS, note the following:

• The JAWS button list dialog contains all active buttons, which may be a lengthy list.

• Except for the page heading, the OEDA Web interface does not contain HTML headings (<H2>, <H3>, and so on). Therefore, you cannot navigate using HTML headings within JAWS.

• The OEDA Web interface does not contain any links. Therefore, you cannot navigate using links within JAWS.