| Note |
|---|
This page is outdated and no longer receives updates! |
This is meant to be a page to describe how to monitor your different instances of OpenMRS (and perhaps other hardware or software) to ensure it's up and running.
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| Code Block |
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#!/bin/sh
url='http://localhost:8080/openmrs/index.htm';
timeout=5; # seconds allowed before giving up
status=$(IFS=' ';r=($(curl -Is --connect-timeout ${timeout} "${url}" || echo 1 500));echo ${r[1]});
if [ $status -eq 500 ]; then
/etc/init.d/tomcat6 restart
fi
|
For
...
ubuntu,
...
if
...
you
...
save
...
that
...
script
...
(setting
...
URL
...
to
...
the
...
exact
...
URL
...
of
...
the
...
page
...
you
...
want
...
to
...
test)
...
into
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/etc/init.d/cron.hourly,
...
then
...
tomcat6
...
should
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get
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restarted
...
if
...
the
...
page
...
doesn't
...
load.
...
You
...
could
...
play
...
with
...
cron
...
and
...
make
...
it
...
run
...
more
...
frequently,
...
but
...
beware
...
that
...
this
...
could
...
try
...
to
...
restart
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tomcat6
...
each
...
time
...
it
...
is
...
run
...
if
...
OpenMRS
...
isn't
...
working.
...
Also
...
note
...
that
...
the
...
URL
...
should
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be
...
a
...
final
...
URL
...
and
...
not
...
a
...
redirect
...
(e.g.,
...
http://localhost:8080/openmrs/
...
is
...
not
...
a
...
final
...
URL;
...
rather,
...
it
...
redirects
...
you
...
to
...
another
...
URL).
...
Cheers,
...
-Burke
...
For
...
those
...
interested
...
in
...
how
...
this
...
line
...
works:
...
status=$(IFS='
...
';r=($(curl
...
-Is
...
--connect-timeout
...
${timeout}
...
"${url}"
...
||
...
echo
...
1
...
500));echo
...
${r[1]});
...
I'll
...
break
...
it
...
down…working
...
from
...
the
...
inside
...
out:
...
curl
...
-Is
...
--connect-timeout
...
${timeout}
...
"${url}"
...
uses
...
the
...
curl
...
command
...
to
...
fetch
...
the
...
URL,
...
waiting
...
up
...
to
...
TIMEOUT
...
seconds
...
for
...
it
...
to
...
respond.
...
Option
...
-I
...
makes
...
it
...
return
...
HTTP
...
headers
...
and
...
-s
...
silences
...
output
...
like
...
a
...
progress
...
bar.
...
The
...
HTTP
...
output
...
starts
...
with
...
something
...
like
...
"HTTP/1.1
...
200
...
OK",
...
where
...
the
...
second
...
word
...
is
...
the
...
status
...
code
...
that
...
we
...
want.
...
||
...
echo
...
1
...
500
...
follows
...
the
...
curl
...
command,
...
using
...
the
...
scripting
...
"or"
...
operator
...
(||)
...
to
...
return
...
"1
...
500"
...
if
...
the
...
curl
...
command
...
comes
...
up
...
empty.
...
The
...
"1"
...
is
...
a
...
dummy
...
value,
...
since
...
we
...
want
...
"500"
...
as
...
the
...
second
...
word
...
in
...
this
...
output
...
to
...
mimic
...
a
...
HTTP
...
internal
...
server
...
error
...
code
...
500.
...
The
...
above
...
is
...
wrapped
...
in
...
a
...
$()
...
to
...
execute
...
the
...
command
...
and
...
its
...
output
...
is
...
assigned
...
to
...
the
...
variable
...
r.
...
The
...
preceding
...
IFS='
...
'
...
sets
...
the
...
input
...
field
...
separator
...
to
...
split
...
the
...
subsequent
...
command's
...
output
...
on
...
spaces
...
--
...
in
...
other
...
words,
...
thanks
...
to
...
the
...
IFS='
...
',
...
the
...
output
...
of
...
the
...
curl
...
command
...
is
...
broken
...
apart
...
into
...
separate
...
words.
...
Finally,
...
the
...
echo
...
${r[1]}
...
command
...
at
...
the
...
end
...
takes
...
the
...
value
...
of
...
variable
...
r
...
(our
...
curl
...
output,
...
broken
...
into
...
words),
...
retrieves
...
the
...
second
...
word
...
(we
...
geeks
...
start
...
numbering
...
at
...
zero,
...
so
...
"1"
...
is
...
the
...
second
...
word),
...
and
...
echoes
...
it
...
into
...
the
...
status
...
variable.
...
When
...
the
...
line
...
is
...
done
...
executing,
...
we
...
either
...
have
...
the
...
HTTP
...
status
...
code
...
(200
...
is
...
good,
...
500
...
is
...
bad)
...
in
...
the
...
status
...
variable.
Another approach
Not sure if this is providing a deeper check, but I was invoking a full login request to make sure the whole stack is working. Together with some mail notification and a double check if the system is really down I wrote down a few more lines. Hourly invoked through a cronjob it does want I needed for now.
Just in case someone wants to have an old-school alternative to the fancy curl statement...
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