Can anyone provide some advice please, we have a load balanced Alfresco CE 4 environment using Solr for indexing. The environment has two front end Alfresco servers, each pointing to their own solr server. The Alfresco environments are synchronized, however we are seeing a difference in the stats and disk space used on the solr servers. 4GB of disk space used more in solr server 2 even though the stats indicate 41558 less documents. Is it worth running a repair on the indexes? re-building the indexes takes 4-5 days and leaves the system unusable so didn't really want to go down that road unless essential.
When you say that reindexing leaves the system unusable is because the process consumes a lot of resources, right?
If you cannot reindex to have both SOLR Indexes paired, then you can inspect every node to identify and classify the errors.
What looks weird is that maxDoc in Node 1 is 2... but 3... in Node 2. This number should be, more or less, the same, as is the max value for the ID in the table ALF_NODE.
If you trust server 2, I would recommend copying the index directories from that server to server 1. This is a well known procedure during upgrades of clusters (that is, creating the index in a single server, and then copy the files to the other servers).
As usual, keep a backup copy of index 1, just in case. Ideally, you should stop both servers before getting the backup and performing the copy of the files. Although that may mean a short period of down time, it will be much faster that performing a full reindex.
Let us know how it went.