< Previous  | TOC | Index | Next  >

Displaying network performance data

The vxrlink stats command reports detailed information about the state of the network. It displays network statistics that can be used to assess network problems. Use the network performance data to determine the optimum network configuration for efficient use of system resources.

The vxrlink stats command can be executed repeatedly at given intervals using the -i interval option. In this case, the displayed values indicate the change since the last interval, except for the average round-trip value, which displays a moving average. The vxrlink stats command can be executed from the Primary and the Secondary. The RLINK statistics are reset when the RLINK disconnects. For detailed information on available options, refer to the vxrlink manual page.

The output of the vxrlink stats command includes the following details:

• Number of messages transmitted.
• Number of 512-byte blocks transmitted.
• Average round-trip per message.
  The size of the message affects the average round-trip per message.
• Number of timeouts or lost packets.
  If the number of timeouts is high, it indicates that network is very lossy. This needs to be fixed.
• Number of stream errors
  Stream errors occur when the RLINK attempts to send messages faster than the network can handle.
• Number of memory errors
  Memory errors occur when the secondary has insufficient buffer space to handle incoming messages. To reduce the number of errors, try increasing the value of the tunable, vol_max_nmpool_sz on the secondary.
• Current Timeout Value
  This represents the packet timeout in milliseconds.