(r6) ChangeSeName < LCG

LCG Web>LCGGridDeployment>LCGSoftware>DataManagementTop>DataManagementDocumentation>ChangeSeName (revision 6) (raw view)~~EditAttachPDF~~
---+ Storage Element (SE) name change

In case the FQDN of a SE changes, some entries need to be modified in the LFC databases.
<br />
---++ Oracle LFC
In this section you describe how to the update with an Oracle LFC.<br /><br />

---

---+++ Presentation of the script<br />

This is taken care of automatically by the =PL/SQL script update_sfn_path.sql=.

It is not yet included in any =LFC= RPM, but can be found in the [[http://jra1mw.cvs.cern.ch:8180/cgi-bin/jra1mw.cgi//LCG-DM/scripts/change-se-name/][gLite CVS repository]] :
   * under LCG-DM/script/change-se-name

This script is composed of two functions:<br />
   * *update_host_name* (<span style="color: blue;">host_to_replace</span> varchar2, <span style="color: red;">host_name_replacing</span> varchar2) which allows replacing the Cns_file_replica.host column = <span style="color: blue;">host_to_replace</span> with <span style="color: red;">host_name_replacing</span>;
   * *update_sfn* (<span style="color: blue;">sfn_prefix_to_replace</span> varchar2, <span style="color: red;">sfn_prefix_replacing </span>varchar2, host_cond varchar2 default NULL) which allows replacing the Cns_file_replica.sfn column starts with <span style="color: blue;">sfn_prefix_to_replace <span style="color: black;">with </span></span><span style="color: red;">sfn_prefix_replacing<span style="color: black;">. An extra condition must be given is the host entry.</span><br /></span>

---

---+++ Installation of the script (to do only the first time)<br />

As it is a PL/SQL script, it needs to be compiled on the DB. To do so, launch a sqlplus command line and connect to the DB. Then type, @&lt;path_to_plsql_script&gt;/update_sfn_path.sql.

<br />
---+++ Example of usage<br />
---++++ Updating the host name
To change the host lxb5409.cern.ch to lxn1177.cern.ch, you need to do as follows:<br /><br /> <verbatim>
sqlplus> set serveroutput on;
sqlplus> set variable rescode varchar2(1000);
sqlplus> exec :rescode:=update_host_name('lxb5409.cern.ch','lxn1177.cern.ch');
sqlplus>print rescode;
</verbatim> The script should return rescode=SUCCESSFUL_UPDATE if the update has been done correctly.

*Note:* with Oracle version > 10.2.0.4, =set variable rescode ...= doesn't work. Use =variable rescode ...= instead.

---++++ Updating the sfn entries
There are two possible scenarii: <br />
   * I want to replace all the sfns which *start with* srm://sc.cr.cnaf.infn.it/castor/cnaf.infn.it/grid/lcg/atlas/datafile with srm://storm-fe.cr.cnaf.infn.it/atlas/datafiles/.
 You need to use the script as follows: <verbatim>
sqlplus> set serveroutput on;
sqlplus> set variable rescode varchar2(1000);
sqlplus> exec :rescode:=update_sfn('srm://sc.cr.cnaf.infn.it/castor/cnaf.infn.it/grid/lcg/atlas/datafile/','srm://storm-fe.cr.cnaf.infn.it/atlas/datafiles/');
sqlplus>print rescode;
</verbatim> The script should return rescode=SUCCESSFUL_UPDATE if the update has been done correctly.<b><br /></b>

*Note:* with Oracle version > 10.2.0.4, =set variable rescode ...= doesn't work. Use =variable rescode ...= instead.

   * I want to replace all the sfns which *start with* srm://sc.cr.cnaf.infn.it/castor/cnaf.infn.it/grid/lcg/atlas/datafile with srm://storm-fe.cr.cnaf.infn.it/atlas/datafiles/ *AND* which are located on host='DCTAPE_00'

You need to use the script as follows:
<verbatim>
sqlplus> set serveroutput on;
sqlplus> set variable rescode varchar2(1000);
sqlplus> exec :rescode:=update_sfn('srm://sc.cr.cnaf.infn.it/castor/cnaf.infn.it/grid/lcg/atlas/datafile/','srm://storm-fe.cr.cnaf.infn.it/atlas/datafiles/','DCTAPE_00' );
sqlplus>print rescode;
</verbatim> The script should return rescode=SUCCESSFUL_UPDATE if the update has been done correctly.

*Note*: in the two previous scenarii, if you have already registered your new sfn, the script deletes the entry with the old sfn.

*Note:* with Oracle version > 10.2.0.4, =set variable rescode ...= doesn't work. Use =variable rescode ...= instead.

---++ !MySQL LFC

If you have a !MySQL LFC, you can do as follows:<br />

<verbatim>
mysql> use cns_db
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> update Cns_file_replica set sfn = replace(sfn,'sfn://se01.cern.ch/old/path/','srm://new-se01.cern.ch/my/new/path/');
Query OK, 38 rows affected (0.01 sec)
Rows matched: 2107  Changed: 38  Warnings: 0

mysql> update Cns_file_replica set host = replace(host,'se01.cern.ch','new-se01.cern.ch');
Query OK, 38 rows affected (0.01 sec)
Rows matched: 2107  Changed: 38  Warnings: 0
</verbatim>

If you have millions of entries then you need to limit the number of rows to update via limit and retype the command unitl you see *0 rows affected*


<verbatim>
mysql> use cns_db
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> update Cns_file_replica set sfn = replace(sfn,'sfn://se01.cern.ch/old/path/','srm://new-se01.cern.ch/my/new/path/') limit 1000;
Query OK, 1000 rows affected (0.01 sec)
Rows matched: 32000  Changed: 1000  Warnings: 0

mysql> update Cns_file_replica set sfn = replace(sfn,'sfn://se01.cern.ch/old/path/','srm://new-se01.cern.ch/my/new/path/') limit 1000;
Query OK, 1000 rows affected (0.01 sec)
Rows matched: 32000  Changed: 1000  Warnings: 0

mysql> update Cns_file_replica set sfn = replace(sfn,'sfn://se01.cern.ch/old/path/','srm://new-se01.cern.ch/my/new/path/') limit 1000;
Query OK, 0 rows affected (0.01 sec)
Rows matched: 32000  Changed: 1000  Warnings: 0

</verbatim>
<b><br /></b>

*WARNING:* if the new files have already been registered in the LFC, you will get a unique violated constraint, to circumvent it, you need to delete the old entries first and then run the update command.



<br />

---

---++ Checks that you can perform afterwards

   * You can rerun the script and check that no entries have been left out. you should of course get that there are no entries to update
   * You can connect directly to the database and check that the HOST field of the main table returns the correct entry (same remark for the sfn column). 
<verbatim>
select count(*) from Cns_file_replica where HOST='oldSE.cern.ch';
</verbatim>

---

---++ Troubleshooting

In case the script complains about =NLS_XXXX= parameters, just unset all the =NLS_XXXX= environment variables before running the script :

<verbatim>
unset NLS_LANG
unset ORA_NLS33
unset NLS_DATE_FORMAT
</verbatim>

---

---++ Help !

In case of problems, contact helpdesk@ggus.org (remove the NOSPAM !) : your ROC will help you and contact the appropriate experts if needed.

---

-- Main.SophieLemaitre - 06 Jul 2006
Topic revision: r6 - 2008-04-02 - SophieLemaitre
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