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You can use the vxrlink stats command with the -e option to generate extended statistics, in addition to the statistics generated by the vxrlink stats command. The output generated by this command can be useful in assessing the reason for failure at the time it occurred.
The vxrlink stats -e 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. The vxrlink stats -e command can be executed from the Primary as well as the Secondary. The RLINK statistics are reset when the RLINK disconnects.
For detailed information about the available options, refer to the vxrlink manual page.
The output of the vxrlink stats -e command is displayed under the headings Messages and Errors. Each of these headings has the appropriate fields to display the required information. The first is the Messages heading which displays the following information:
Displays the number of 1024 bytes that have been transmitted. This is different from the Blocks attribute displayed by the vxrlink stats command (without the -e option), which only displays the number of blocks that have been acknowledged.
The Messages heading is followed by the Errors heading. It has nine fields that display the different kinds of error encountered, three of which are similar to that in the vxrlink stats command. The output includes the following details:
This error occurs when there is no space in the systems kernel memory to process the message.
This error occurs if there is no memory to store the packets of the message that have arrived out of sequence. If a packet arrives out of sequence then it requires to be stored in the message buffer until all the related out-of-sequence packets arrive and can be assembled.
nmcom pool on Secondary
The buffer space determined by the VVR tunable vol_max_nmpool_sz is already full and cannot store any new messages that arrive at the Secondary.
Indicates the number of timeout errors, that is, the number of times the Primary timed out while waiting for an acknowledgement from the Secondary.
Indicates the number of times the last packet of a message was received, before one or more packets of the same message were received.
Indicates the number of times messages have arrived out of sequence.
Stream errors occur when the RLINK attempts to send messages faster than the network can handle.
Displays the number of data checksum errors. Every time a packet is received at the Secondary VVR performs a checksum to ensure that the packet data is the same as that sent by the Primary.
Displays the number of times the packets could not be delivered to the Secondary, due to transaction errors. If the Secondary is busy with some kernel operations when the packet arrives at the Secondary, then these packets may not be delivered until the transaction is complete.