Replication Troubleshooting (4035193)

Replication refers to the transfer of data over a port from one location to another.  Although both the repository and Core are assigned a GUID, communication is handled via TCP/IP.  Any issues that may cause communication difficulties within that protocol will therefore affect replication.

The following section details various troubleshooting steps you can take to determine a possible cause for replication issues (note that the below steps exclude potential timeout and semaphore issues).

Replication runs over port 8006, which is the default port for all backups in AppAssure 5.

• Multiple concurrent backup jobs, including any active checks and scans, will delay, slow down, or disrupt replication. Checking the timing of replication against active backups can point to the issue.
  In this case, simply lower the Maximum Concurrent Transfers.
  • Click on the Configuration tab and navigate to Settings > Transfer Queue
  • Click on Change and Adjust the transfer settings.
    
• Telnetting via port 8006 from Source Core to Target Core (or telnet/ping from each Core to its associated repository) may show connection issues as well. Note that ping runs on its own dedicated port, so you may see ping function normally while telnet fails.
• System resources and I/O may cause timeouts and slow transfer speeds. 
  This is reflected in the AppAssure 5 Sizing Guide.
• Traceroute is also a useful tool in troubleshooting replication issues. 
  ‘tracert *location*’ is the format for it.  It gives a step by step (or hop by hop) report of the ping times from one location to another.
• One item to keep in mind regarding WAN replication is that there have been occasions were the Target Core is housed within either a residence or a location that has a residential ISP.  That may be attractive from a budget perspective, but it will not work with AppAssure replication. Port ranges that AppAssure requires are blocked by residential ISPs due to state and government regulations.  This has been confirmed by both US and Canada internet service providers.

The following articles may also be of use:

• AppAssure 5 Firewall Port Requirements
• Port 8006 Troubleshooting