Details about ELOG, our E949  electronic logbook 
------------------------------------------------

Renee Poutissou,   updated 01-mar-2002

ELOG is implemented via the MIDAS DAQ system. 
The ODB (online data base) of MIDAS resides on bnlku33
in ~bnlonl/online_midas and the files reside on 
/e949dsk/data_midas/hdb1

The interface to ELOG is done throuth any web browser 
connecting to  
   http://bnlku33.phy.bnl.gov:8081/EL/?exp=E949 (for bnl.gov)
or
   http://bnlku28.phy.bnl.gov:8081/EL/?exp=E949 (for outside)
The interface is self-explanatory 


Inputting information to ELOG
----------------------------
Information can be entered into ELOG via any web browser selecting
the "New" button or via command line using melog.
Type "melog -h" for description of options 

Example using "melog"
melog -h bnlku33 -p 8081 -l E949 -a author=online_script -a Type=Routine -a System=DAQ  -a Subject="EOR" "Stopping run"

How does it work
----------------
Input received via the web server (mhttpd) or the task (melog) is 
appended to a file in the directory defined in the ODB as 
"/Logger/Data dir". This is now /e949dsk/data_midas/hdb1 
The filename is YYMMDD.log where YY is the last 2 digit of year, 
MM is the month and DD is the day, ex 7-jan-2002 --> 020107.log
If the date changes when a new entry is submitted, a new file is started. 

If attachements are submitted with any entry, the attachments are
copied to the "/Logger/Data dir" under a name starting with the 
YYMMDD; ex : /data_midas/hdb1/020204_142234_delco_1_17a.ps 

Source code:
bnlku33:  /e787dsk/e787d/bnlonl/online_midas/midas/src/mhttpd.c
bnlku28:  /e787dsk/e787d/bnlonl/online_midas/midas_bnlku28/src/mhttpd.c
bnlku9/7: /e787dsk/disk1/online.7x/midas/utils/melog.c

ELOG parameters
---------------
There are some setup parameters for ELOG in the ODB.
The parameters are 
      Display run number       y
      Allow delete             n
      Types                    [0] Routine
                               [1] Glitch
                               .....
                               [19]
      Systems                  [0] General
                               [1] DAQ
                               ......
                               [19]

To add a new "Types", enter an ASCII string in the first blank
element, same thing for "Systems". There can be at most 20 Types
and 20 Systems. These tags are useful for the "Query" command
 
You can access these tags via the command line command "odb"
or from the web STATUS
- Command line mode:
 -------------------
bnlku33 > odb
[local:E949:R]/>cd elog
[local:E949:R]/Elog>ls
Display run number              y
.....
[local:E949:R]/Elog>set Types[5] "New type"
[local:E949:R]/Elog>exit
bnlku33>

- Web page:
  --------- 
Select Status
  Select ODB
      Select Elog
         Select the entry you want to change, this is
usually the first occurence of "(empty)" in Types or Systems

- Backup copy of ELOG files:
----------------------------
There is a mirror copy of all ELOG files made via a cron job.
The cronjob is setup by ~bnlonl/online_midas/bin/crontab_bnlku33
which runs every 10 minutes, the script rsync_elog.csh
The mirror copy is located at ~bnlonl/online_logfiles/elog


- Troubleshooting
-----------------
Usually the problem is that something is not working or seems
wrong when using a web browser interface. That is due to some
problem with the web server program called mhttpd. 
One solution is to restart this program:
- Sign on to bnlku33 (or bnlku28 depending on what machine you 
are pointing at) as user bnlonl
- >cd online_midas/bin
- >restart_mhttpd