DLC Status Information
For a service access point (SAP) or a link station (LS), you can obtain the status information.
Status information can be obtained for a service access point (SAP) or a link station (LS) using the DLC_QUERY_SAP and DLC_QUERY_LS ioctl subroutines to call the specific DLC kernel device manager in use.
The DLC_QUERY_SAP ioctl subroutine obtains individual device driver statistics from various devices:
- Token ring (See Token-Ring Data Link Control Overview)
- Ethernet (See IEEE 802.3 Ethernet Data Link Control Overview)
- Multiprotocol (See Multiprotocol in AIX® Version 7.1 Kernel Extensions and Device Support Programming Concepts)
The DLC_QUERY_LS ioctl subroutine obtains LS statistics from various DLCs. These statistics include data link protocol counters. Each counter is reset by the DLC during the DLC_START_LS ioctl subroutine and generally runs continuously until the LS is terminated and its storage is freed. If a counter reaches the maximum count, the count is frozen and no wraparound occurs.
The suggested counters provided by a DLC device manager are listed as follows. Some DLCs can modify this set of counters based on the specific protocols supported. For example, the number of rejects or receive-not-ready packets received might be meaningful.
| Item | Description |
|---|---|
| test commands sent | Contains a binary count of the test commands sent to the remote station by GDLC, in response to test commands issued by the user. |
| test command failures | Contains a binary count of the test commands that did not complete properly due to
problems such as:
|
| test commands received | Contains a binary count of valid test commands received, regardless of whether the response is completed correctly. |
| sequenced data packets transmitted | Contains a binary count of the total number of normal sequenced data packets transmitted to the remote LS. |
| sequenced data packets retransmitted | Contains a binary count of the total number of normal sequenced data packets retransmitted to the remote LS. |
| maximum contiguous retransmissions | Contains a binary count of the maximum number of times a single data packet has been retransmitted to the remote LS before acknowledgment. This counter is reset each time a valid acknowledgment is received. |
| sequenced data packets received | Contains a binary count of the total number of normal sequenced data packets correctly received. |
| invalid packets received | Contains a binary count of the number of invalid commands or responses received, including invalid control bytes, incorrect I-fields, and overflowed I-fields. |
| adapter-detected receive errors | Contains a binary count of the number of receive errors reported back from the device driver. |
| adapter-detected transmit errors | Contains a binary count of the number of transmit errors reported back from the device driver. |
| receive inactivity timeouts | Contains a binary count of the number of receive time outs that have occurred. |
| command polls sent | Contains a binary count of the number of command packets sent that requested a response from the remote LS. |
| command repolls sent | Contains a binary count of the total number of command packets retransmitted to the remote LS due to a lack of response. |
| command contiguous repolls | Contains a binary count of the number of times a single command packet was retransmitted to the remote LS due to a lack of response. This counter is reset each time a valid response is received. |