Wikis content not accessible…
it`s been quite a long time; many projects at the moment so that blogging needs to wait 😉
Last week we had a very interesting problem at one customer’s environment. When accessing a Wiki, the page was displayed blank – no content was available. Browsing to older versions of this wikis worked.
The error in the log:
Parsing error… Wikis content (the body) gets store in the filesystem as xml files. If you access a Wiki there is a XML parser that first checks the syntax – then the xml file is converted to HTML and you can view the content.
When analyzing this deeper we figured out that this has something to do with a maintenance we did on the same day, where a highly available NFS cluster was replaced by another NFS solution. It turned out that the old cluster had synchronization issues with some files so that some content was not available on both nodes. When migrating this content we took one of the old NFS servers and just installed the new NFS software onto this. Strangely the old NFS cluster created the files on both NFS servers but on one side without content – we had 0 KB files.
This explains the parsing error we saw in the log. Because the parser finds the file – but for sure it is not parse able (0KB content)!
The issue was solved by resyncing the old file store so that both sides were synchronous and then migrate the content again.
Maybe this helps someone out there… If you get a SAX parsing error, look for 0 KB files 😉