Description of problem:

I've tried to run cpdb --update and I'm getting an error (see below). A couple minutes ago the update was successful.

I've noticed that by the time of this error, I'm getting 503 when requesting http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-2.0.xsd Service Temporarily Unavailable.

I would expect that running an update script should not be dependent on availability of some external service.


########## ERROR ############
Error running command: liquibase --driver=org.postgresql.Driver --classpath=/usr
/share/java/postgresql-jdbc.jar:/var/lib/tomcat6/webapps/candlepin/WEB-INF/class
es/ --changeLogFile=db/changelog/changelog-update.xml --url=jdbc:postgresql:cand
lepin --username=candlepin migrate
Status code: 65280
Command output: INFO 5/3/12 10:39 AM:liquibase: Successfully acquired change log
 lock
WARNING 5/3/12 10:40 AM:liquibase: schema_reference.4: Failed to read schema doc
ument 'http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-2.0.xsd', because
 1) could not find the document; 2) the document could not be read; 3) the root 
element of the document is not <xsd:schema>.
INFO 5/3/12 10:40 AM:liquibase: Successfully released change log lock
Liquibase Update Failed: schema_reference.4: Failed to read schema document 'htt
p://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-2.0.xsd', because 1) could 
not find the document; 2) the document could not be read; 3) the root element of
 the document is not <xsd:schema>.
SEVERE 5/3/12 10:40 AM:liquibase: schema_reference.4: Failed to read schema docu
ment 'http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-2.0.xsd', because 
1) could not find the document; 2) the document could not be read; 3) the root e
lement of the document is not <xsd:schema>.
liquibase.exception.ChangeLogParseException: Error parsing line 2 column 255 of 
db/changelog/changelog-update.xml: schema_reference.4: Failed to read schema doc
ument 'http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-2.0.xsd', because
 1) could not find the document; 2) the document could not be read; 3) the root 
element of the document is not <xsd:schema>.
        at liquibase.parser.core.xml.XMLChangeLogSAXParser.parse(Unknown Source)

        at liquibase.Liquibase.update(Unknown Source)
        at liquibase.integration.commandline.Main.doMigration(Unknown Source)
        at liquibase.integration.commandline.Main.main(Unknown Source)
Caused by: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 255; sche
ma_reference.4: Failed to read schema document 'http://www.liquibase.org/xml/ns/
dbchangelog/dbchangelog-2.0.xsd', because 1) could not find the document; 2) the
 document could not be read; 3) the root element of the document is not <xsd:sch
ema>.

Additional info: