I cc'ed the las_users group as it seems like a worthwhile topic.
I have a machine that is running half a dozen LAS 5's and half a dozen LAS 6's without any problems at all. Each LAS has a separate installation directory and I run configure in each. I use the same Apache server and same MySQL server for all of the LAS's. For the v6 servers I force them to share a single Tomcat server.
Each time you run the configure script for a new LAS installation, a MySQL database named 'las' has it's 'map' table updated to associate a .xml configuration file with another database named 'las#'. If the .xml configuration file is new then a the # is incremented. Each 'las#' database associated with the 'las.xml' configuration file has tables that contain the information about datasets, variables, properties, etc. associated with that LAS installation.
So there should be no problems at all with running multiple LAS installations
with a single MySQL installation. Just install LAS in a new directory
and give it a new name like "las2" in the configuration process.
And don't forget to update the Apache httpd.conf file.
-- Jon
For the interested I'll include a short tour of the LAS MySQL tables that will explain what is going on.
Using the appropriate localhost/full_host as appropriate, you should be able to do the following:
> mysql -u root -h localhost -p
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 12162 to server version: 3.23.45
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> show databases;
+----------+
| Database |
+----------+
| bugs |
| bugs2 |
| las |
| las0 |
| las1 |
| las10 |
| las11 |
| las12 |
| las13 |
| las14 |
...
44 rows in set (0.00 sec)
### We've got a bunch of LAS installations on this computer.
### Some of them are defunct but I've not bothered to clean up
### their old entries in this table. The database named 'las'
### is the place to begin.
mysql> use las;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+---------------+
| Tables_in_las |
+---------------+
| map
|
| sessions |
+---------------+
2 rows in set (0.00 sec)
mysql> describe map;
+-------+--------------+------+-----+---------+-------+
| Field | Type
| Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| urlid | varchar(128) | | PRI |
| |
| path | varchar(255) | |
| |
|
| dbase | varchar(32) | YES |
| NULL | |
+-------+--------------+------+-----+---------+-------+
3 rows in set (0.00 sec)
mysql> select * from map;
+------------------------+----------------------------------------------------------------------------------------------------------+-------+
| urlid
| path
| dbase |
+------------------------+----------------------------------------------------------------------------------------------------------+-------+
| ayIcAjUHdfbulHjY5FNSCQ | file:/home/stout/sirott/lasxml/server/las.xml
| las0 |
| IBFCTw/aa3d4ZmmMB/2GbA | file:/home/stout/sirott/lasxml/server/ui.xml
| las1 |
| fWQvk+dv4sphTpZKeQLdVw | file:/home/stout/sirott/lasxml/server/options.xml
| las2 |
| UfY6W6eqs7k44y1T20SMyA | file:/home/stout/sirott/las_servlet/perl/las.xml
| las3 |
| 9lKYAKY7HPUiiyqvuqg/oQ | file:/home/stout/sirott/las/server/las.xml
| las4 |
| LbWq/VttBQLywRQGE2UdWA | file:/home/stout/sirott/las/server/ui.xml
| las5 |
...
38 rows in set (0.01 sec)
### As you see in the above commands, the 'las' database
### associates a unique path with another mysql database where
all
### of the information for that LAS installation reside.
### Let's look at the one whose configuration file is:
### /home/stout/sirott/las/server/las.xml
mysql> use las0;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+----------------+
| Tables_in_las0 |
+----------------+
| attributes |
| children |
| elements |
+----------------+
3 rows in set (0.01 sec)
### The 'elements' table is the place to begin but I'll give
### you a shortcut by saying just select rows that describe
### the variables associated with a dataset;
mysql> describe elements;
+-------+--------------+------+-----+---------+-------+
| Field | Type
| Null | Key | Default | Extra |
+-------+--------------+------+-----+---------+-------+
| oid | int(11) |
| PRI | 0 |
|
| name | varchar(128) | | MUL
| |
|
| path | varchar(255) | | MUL
| |
|
+-------+--------------+------+-----+---------+-------+
3 rows in set (0.00 sec)
mysql> select * from elements where name = "variables";
+-----+-----------+-----------------------------------------------------+
| oid | name | path
|
+-----+-----------+-----------------------------------------------------+
| 153 | variables | /lasdata/datasets/coads_climatology_cdf/variables
|
| 221 | variables | /lasdata/datasets/levitus_climatology_cdf/variables
|
+-----+-----------+-----------------------------------------------------+
2 rows in set (0.04 sec)
### Armed with the object ID (oid) we can query the 'children' table
### to see what variables are in the coads_climatology_cdf dataset.
mysql> describe children;
+-----------+--------------+------+-----+---------+-------+
| Field | Type
| Null | Key | Default | Extra |
+-----------+--------------+------+-----+---------+-------+
| oid | int(11)
| | | 0
| |
| parentid | int(11) |
| MUL | 0 |
|
| childid | int(11) |
| MUL | 0 |
|
| childname | varchar(128) | |
| |
|
+-----------+--------------+------+-----+---------+-------+
4 rows in set (0.00 sec)
mysql> select * from children where parentid = "153";
+-----+----------+---------+-----------+
| oid | parentid | childid | childname |
+-----+----------+---------+-----------+
| 156 | 153 |
155 | airt |
| 163 | 153 |
162 | speh |
| 170 | 153 |
169 | sst |
| 177 | 153 |
176 | uwnd |
| 184 | 153 |
183 | wspd |
| 191 | 153 |
190 | vwnd |
| 198 | 153 |
197 | slp |
+-----+----------+---------+-----------+
7 rows in set (0.02 sec)
John C Cartwright wrote:
Thanks for the prompt reply, Jon.My problem is that during the transition period between versions 5 and
6, I'd like to run both las5 and las6 on the same server.It was not clear to me where (other than mysql hostname) I could direct
the las6 configure script to use a different set of databases. If I had
to, I could run a separate instance of mysql on a different port, but
couldn't even see where I'd specify it if I did.Do you have any suggestions of how best to deal with this situation?
Thanks!
-- john
----- Original Message -----
From: "Jonathan S Callahan" <Jonathan.S.Callahan@noaa.gov>
Date: Monday, March 3, 2003 11:31 am
Subject: Re: sharing a database between las5 and las6> John,
>
> It's definitely not advisable to do this. You'd probably have to
> hack to
> code to make it work and I see no reason why you'd want to do this.
> Can
> you describe the problem you're trying to solve with this so that
> we might
> suggest another solution?
>
>
> -- Jon
>
>
> John C Cartwright wrote:
>
> > Hello All,
> >
> > I was wondering if it were possible or advisable, to share a
> single set
> > of mysql databases (las, las0, las1, etc.) between a instance of
> las5> and las6 running on the same server.
> >
> > Thanks!
> >
> > -- john
>
>