From 67540970f7c8c91d45f7060e5fe4fb79d4ea7c19 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ale=C5=A1=20K=C5=99enek?= Date: Mon, 7 Jul 2008 16:21:38 +0000 Subject: [PATCH] muliple instances and backup dumps --- org.glite.lb.doc/src/LBAG-Installation.tex | 4 +++ org.glite.lb.doc/src/LBAG-Running.tex | 53 +++++++++++++++++++++++++++++- 2 files changed, 56 insertions(+), 1 deletion(-) diff --git a/org.glite.lb.doc/src/LBAG-Installation.tex b/org.glite.lb.doc/src/LBAG-Installation.tex index 535b8ed..33fd5c6 100644 --- a/org.glite.lb.doc/src/LBAG-Installation.tex +++ b/org.glite.lb.doc/src/LBAG-Installation.tex @@ -69,7 +69,11 @@ transakce \subsubsection{Export to R-GMA} +\subsubsection{Data backup} +\label{inst:backup} + \subsubsection{Purging old data} +\label{inst:purge} \TODO{Setup cron job, refer to Sect.~\ref{maintain:purge}} diff --git a/org.glite.lb.doc/src/LBAG-Running.tex b/org.glite.lb.doc/src/LBAG-Running.tex index 395d9c4..9f6d467 100644 --- a/org.glite.lb.doc/src/LBAG-Running.tex +++ b/org.glite.lb.doc/src/LBAG-Running.tex @@ -96,11 +96,62 @@ user & \emph{arbitrary} & arbitrary user tag \\ % lze to, i nad jednou databazi, zadna automaticka podpora +Specific conditions (\eg debugging, different authorization setup, \dots) +may require running multiple \LB server instances +on the same machine. +Such setup is available, however, there is no specific support in automated +configuration, the additional non-default server instances must be run manually. + +The other server instance must use different ports (changed with \verb'-p' +and \verb'-w' options), as well as use different pid file (\verb'-i' option). + +The servers may or may not share the database (non-default is specified +with \verb'-m')% +\footnote{Even when sharing the database, the servers are still +partially isolated from +one another, \eg a~job \url{https://my.machine:9000/xyz} cannot be queried +as \url{https://my.machine:8000/xyz}. +However, due to implementation internals, the second job cannot be registered.}. + \subsubsection{Backup dumps} -Denni dumpy (ne purge) +(This functionality should not be confused with per-job dumps, Sect.~\ref{inst:purge} and \ref{run:purge}.) + +Besides setting up \LB server database on a~reliable storage or +backing it up directly (Sect.~\ref{inst:backup}) +\LB server supports backing up only incremental changes in the data. +Advantages of this approach are lower volume of data to be backed up, +and possibility to load them to another instance (\eg for heavyweight +queries which should not disturb normal operation), disadvantage is +a~more complex and more fragile setup. + +Using an external utility \verb'glite-lb-dump' (typical invocation is with +a~single option \verb'-m' \emph{my.server.name:port}, see man page for +details) the server is instructed to dump events, which arrived in +a~specified time interval, into a~text file. Default interval is from last +dump till the current time. The events are stored in a~uniquely named text +file prefixed with the value of \verb'-D' server option. This kind of dump +contains events according to their arrival time, regardless of jobs they belong +to. + +It is sufficient to run the dump regularly, with a~frequency matching +an acceptable risk of loosing data (several hours typically), and back up the +resulting dump files. In the event of server crash, the files can be loaded +back into a~restored empty server with complementary \verb'glite-lb-load' +utility. + +Server superuser privileges (X509 credentials) are required to run \verb'glite-lb-dump' and \verb'glite-lb-load'. + +This backup strategy can interfere with too aggressive setting of old +data purging (Sect.~\ref{run:purge}), +If the purging grace period is shorter than the dump interval, +events may get purged before they are captured by the backup dump. +However, this interference is unlikely (reasonable purge grace period +is several times longer than dump period), +and it is not fatal in general (data were purged on purpose either). \subsubsection{Purging and processing old data} +\label{run:purge} \TODO{salvet} -- 1.8.2.3