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Author's profile photo Lloyd Goveia

Tips for using BLV (BCM Log Viewer)

Table of Contents

Introduction // Getting started // Viewing logs // Navigation // Find Window Interface // Simple screening // Basic Call ID trace // Hotkeys


BLV tool (SAP CONTACT CENTER/BCM Log Viewer) is included in every SAP CONTACT CENTER releases. It provides a simple interface and easy to use search functionalities to help with SAP CONTACT CENTER log reading.

Getting started

BLV tool is a single executable file located in the SAP CONTACT CENTER installation package, file path: \Tools And Utilities\blv\blv.exe, so there is no actual installation executable.

Please copy the blv.exe file to a convenient location (eg. desktop), and double click to execute.

If  you would like to add blv into the context menu in Windows Explorer, then there are several options to accomplish this. You can use the Open With / Choose Default program and choose BLV as the default viewer for certain file types, or to show up in the Open With menu.

(lightbulb)One convenient option is to have BLV shown up in the top level of the context menu, regardless of the file type. You can accomplish this with some simple steps in regedit.

  1. Start regedit
  2. Navigate to HKEY_CLASSES_ROOT/*/shell
  3. Add sub key View with BLV
  4. Add sub key View with BLV/command
  5. Edit the (Default) value of the command sub key
  6. Enter the path to BLV plus parameter “%1”
    For example like this: c:\utils\blv "%1"
    Don’t forget the double quotes!
  7. You’re done

Viewing logs

  1. To start viewing SAP CONTACT CENTER log, simply drag a log file into the BLV window, and the log will be displayed.
  2. To view multiple log files simultaneously, you can open multiple BLV windows, and drag logs into each window.
  3. Alternatively, log files (extension .txt and .log) can be directly associated with blv.exe, so double clicking on the log files will open a new BLV window, and display the logs directly.


Normal Windows navigation works in BLV tool: Up and Down arrow keys, Page up and Page down keys, Scroll bar, and mouse scroll wheel.

In addition, the keyboard PgUp/PgDn (will page up and down) and Ctrl+Home/Ctrl+End will go to the start and the end of the file. For a complete list, please refer to the “Hotkeys (Keyboard and Mouse Commands and Command lines)” section.

Find Window Interface

The Find Window can be involved by pressing “Ctrl+F”, where you will see the following screen. From this interface, one can set up keywords, patterns, set new rules, create/edit rule templates, export and import template as well as tag and set highlighting flags for each keyword(s) or patterns used.

  Find Pattern:
this can be used to quickly enter keywords which are automatically highlighted. You can also double-click on a text and after pressing Ctrl+F the field is filled.
tell the tool the sequence in which to do the lookup and if case should be considered
  Create/Delete Rules Template:
using the “+” create new rule (the user can also choose to copy the existing rule as a starting point). With the “-” you can delete existing rules, except the last available one. 
  Exclude Rules:
this will allow users to exclude patterns or keywords to make the trace cleaner in combination with the highlight/collapse rules.
  Highlight/Collapse Rules:
this is the starting point for the keywords/highlight rules creation. Once a template in created, use the fields therein to enter free text keywords and patterns. When the “Apply” button is pressed, the template is then saved. Here as well as under the exclude rule section, the user can choose to select what should be highlighted and what ignore (AC/IC/RE).
  Action Buttons:
with these the user can set the rules active, apply changes, import and *export rules and cancel to exit the find window

Input the desired keyword(s) into the text area on the left hand side; enable option Highlight and Ignore case, then press Find. The keyword will be highlighted in the log. You can also setup “Exclude Rules” to narrow down the trace.

The BLV tool can highlight keywords with up to 10 different colors. When highlighting more than 10 keywords, it is useful to combine similar keywords under one color, e.g.‘ERR>|error|EXC>|exception’.

* When you press [Export] in the Find dialog, a dialog like this will pop up:

Likewise, when you press [Import], a dialog like this will pop up:

There is a wealth of options in both dialogs, but I think their meaning should be pretty evident.

Please note:
As BLV keeps these rules in registry, which is naturally shared by all concurrently running instances of BLV, a few keywords might be good to keep standard because:

  1. At startup, BLV reads all rules from registry
  2. When modifying rules within viewer (e.g. clicking check boxes in status bar), only the current rule set is saved to registry
  3. When opening the find dialog, include and exclude rule sets are read from registry, except  the current ones
  4. When closing the find dialog, all changes are written to registry, except if you close the dialog with [Cancel] or [x]


Simple screening

Keywords “alw>”, “wrn>”, “err>”, and “[EXC]” (all without quotation marks) can be used to quickly screen Alarm, Warning, Error, and Exception messages in the log.

Set up Highlighting/collapse rules for keywords “alw>”, “wrn>”, “err>”, and “[EXC]”, then press “c” on the keyboard, the BLV tool will collapse the log to display only lines containing the keywords. Press “c” again to return to normal mode.

The tool also has a live view move which can be invoked by pressing “l” (letter L) on the keyboard to view the logs in live mode. The combination IC should give live view collapsed.

Time Difference View:

Another cool feature is the Time Difference View. To invoke press Ctrl+R and BLV sets the time reference to the top line and changes to a view that shows for each timestamp line the time difference to the set reference point. This is very handy when troubleshooting timing issues.

If the ‘r’ is pressed, BLV changes to a view that shows for each line the time difference to previous timestamp line.

“Unfolding” in Collapsed View:

This feature is also very nice and can be invoked pressing “g” which gives a view like this:

By pressing ‘g’ again, you can switch back to normal collapsed view.

Basic Call ID trace

Set up Highlighting / collapse rules for a Call ID, then press “c” to view all the relevant log entries for this call. This works well in CEM and Call Dispatch logs, but is less effective in SIP Bridge logs. (SIP messages will be cut off because it does not always contain Call ID)

Hotkeys (Keyboard and Mouse Commands and Command lines)

Press F1 in BLV window to view additional help on hotkeys.



Alt+T Toggle tabs
c Collapse to or in-collapse from matching lines only view
C Collapse to or in-collapse from tagged lines only view
Ctrl+<Nbr> + No selection Toggle highlight <Nbr>
Ctrl+<Nbr> + Selection active Put selection to highlight <Nbr>
Ctrl+C Copy selection to clipboard
Ctrl+Del Clear file (close, truncate and reopen)
Ctrl+End Goto end of file
Ctrl+F Open find dialog or find next occurrence of selected text
Ctrl+Home Goto start of file
Ctrl+Left Scroll page left
Ctrl+Left click Start box selection
Ctrl+N Toggle number highlighting
Ctrl+PageDown Change to next file
Ctrl+PageUp Change to previous file
Ctrl+R Set time reference point and switch to time diff view
Ctrl+Right Scroll page right
Ctrl+S Save selection, marked area, matched or tagged lines to file
Ctrl+Shift+<Nbr> + Selection active Add selection to highlight <Nbr>
Ctrl+Shift+T Clear all tags
Ctrl+T Tag or in-tag top line, or selected lines
Ctrl+WheelDown Decrease font size
Ctrl+WheelUp Increase font size
Down Scroll line down
e Cycle between exclude modes (none / loose / strict)
End Show end of line
Esc Cancel selection and instant highlight
f Find next
F Find previous
F1 Show this help
F3 Open find dialog
F12 Toggle always-on-top mode
g Toggle “unfolding” in collapsed view (show consecutive lines without timestamp after a matched line)
h Cycle between normal, hex and hex-with-line-breaks views
Home Show start of line
l Turn live viewing on or off
Left Scroll column left
Left click Start stream selection
Left DoubleClick Select and instantly highlight word, GUID, timestamp  or text in parents: (…) […] {…} <…>
word = digits letters underscore
GUID = 32 hex digits maybe separated with dashes
timestamp = digit [digit] “:” digit [digit] “:” digit [digit] [ “.” digit [digit [digit]]]
m Start or cancel area marking
M Tag all lines within marked area
o Open font selection dialog
PageDown Scroll page down
PageUp Scroll page up
 r Cycle between time diff views (normal / difference to reference / difference to previous) 
Right Scroll column right
Right Doubleclick Tag or untag line
s Show or hide status line
Shift+F12 Cycle through different window transparency levels
t Goto next tagged line
T Goto previous tagged line
Up Scroll line up
 {empty}  Show all lines
 Ce | CE  


Command Line Syntax

The command line syntax of BLV is:

blv [find=<pattern>] [select=<pattern>] [offset=<number>] filename ...

  • With the find option you can specify a text which BLV searches for and shows in the first specified file.
  • With the select option you can tell BLV to highlight right away the given text in the first specified file.
  • With the offset option you can tell BLV to show the next given file starting from the given offset.

You can also:

  • Combine all of the options, for example, like start a search for some text from some offset and then also highlight some other text.
  • Specify multiple files on the command line, each with their own preceding offset.
  • When you then navigate between files (with Ctrl+PgDn and Ctrl+PgUp) in BLV, it shows each file from the respective offset.

Note that BLV orders the files for navigation in alphabetical order, not in the order they are given on command line.

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      Author's profile photo Tomi Halmela
      Tomi Halmela

      Well done Lloyd,

      Good instructions for a very useful tool. Try out BLV and logs will start to have a new meaning to you. Using BLV is a good way to jump start your CCtr understanding and troubleshooting skills.

      Author's profile photo Lloyd Goveia
      Lloyd Goveia
      Blog Post Author


      Hi Tomi,

      Glad you liked it.

      Yes, this tool is really handy and that’s why we highly recommend our customers get familiar with it to troubleshoot CCtr issues. But you can use it for anything not only CCtr.

      I plan to share another blog with log reading tips and tricks to expand on the BLV usability as well.

      Stay tuned :)….

      Big thanks to Arto Keskiniva for developing the really awesome tool!!
      .... using notepad and notepad++ although they are good for many other things; not so much for 1 gig logs and tracing contacts 🙂


      Author's profile photo Elton Shateri
      Elton Shateri


      Hi Lloyd,

      Very Very good explanation of this tool, This tool is very useful despite the size of the log that the other apps do not open.

      Thank you very much for the explanation

      Author's profile photo Sebastian Alvarez
      Sebastian Alvarez

      Hi Lloyd,


      The tool is very helpful and your explanation is great. We are facing an issue on win 2016 servers, the BLV app suddenly stops working and then when we open it again it crash over and over again, is this a known bug?


      Author's profile photo Lloyd Goveia
      Lloyd Goveia
      Blog Post Author

      Hi Sebastian,

      I have not tested the tool in MS Server 2016 yet so it is possible that there could be an issue. Have you tried with the latest release in FP14?