Communication issues with hubs, robots, and probes

Products

• DX Unified Infrastructure Management (Nimsoft / UIM)
• CA Unified Infrastructure Management On-Premise (Nimsoft / UIM)
• CA Unified Infrastructure Management SaaS (Nimsoft / UIM)

Issue/Introduction

probe throws a communication error. Error messages similar to the following are seen in the tunnel client and tunnel server logs:

hub: sockWrite Failed: 000000000725AD90 <hub IP address>/<port> 10054 (rc = -1, sfd = 6368, lenleft = 246)

Environment

• UIM 8.51 (any release through 9.02)
• hub 7.91 (any version through 7.97)

Cause

- Unknown

Resolution

• It is possible that there is a firewall that is interrupting the communication between the tunnel client hubs and the tunnel server hub, or this issue may be due to network latency.

• The keys to indicate that this might be a firewall issue are the "sockWrite Failed" message string and the lenleft value. Typically these are indicative of a firewall that shuts down the connection which it was still in use.

• This typically occurs with firewalls that are "application aware".

• The following is recommended for firewalls with application aware enabled:

• The firewall rules put in place for UIM ports (48000-48050) should be:

• Idle connection timeout: 7200

• Max connection timeout: 7200

• TCP Connection only : No application awareness (important)

• Note: when application awareness is turned off the max connection & idle connection should be the same.