What to Check if SharePoint is Down

If you're the administrator of your SharePoint farm, you need to know what to do if your farm goes down. Here is a list of the most common causes and what to do about them.

1) On you web front end servers, check the following:

     a) In IIS, are your SharePoint app pools running?
          If no, start them.

     b) In IIS, has your SharePoint site started?
          If no, start the site.

2) On all of your SharePoint servers, has the SharePoint Timer Service and the SharePoint Administration Service started?
     If no, start the services.

3) Are any of your service accounts locked or disabled? Could the passwords have expired recently?
     Try logging in to a server with each service account. do they fail to login? Or, if you have access to Active Directory, check if the service accounts are disabled and re-enable them.

4) On your SQL server, do you have available drive space left for your database files?
     SharePoint stops working if you run out of hard drive space. Free up drive space such as deleting old log files. You can also try shrinking your database in SQL, but this can cause fragmentation of your data. But, sometimes it is necessary when you have limited options.

5) In Central Administration, in the System Configuration page, do any of your server statuses say "Update Required"?
If so, a patch or update was installed recently that may have changed SQL schemas or application files, and the SharePoint Configuration Wizard needs to be run to get SharePoint fully upgraded and in-sync.

6) Can you ping all of your servers?
If not, diagnose the issue. Did firewall rules change? Is the DNS server available? Are physical connections okay? Did your SSL certificates expire? So on...

7) Did new server patches, updates, group policy rules, or a custom application get applied recently?
Verify what was installed, and research the possible affects to SharePoint for each. Rollback changes that may have broke SharePoint.

If none of these items fix your SharePoint farm, check the SharePoint ULS logs and the server's application and security logs for errors. They may point you to the cause of the outage.

I will follow-up this post in the near future with useful ways to gather and read SharePoint ULS logs using PowerShell.

Good luck!
Leo