System Troubleshooting and Diagnostics
5.2 Product Fault Management and Symptom-Directed Diagnosis
Examine the MEMCON software register (
) under the memory subpacket.
The MEMCON register provides memory configuration information and a
MEMORY ERROR STATUS buffer ( ) that points to the memory module(s)
that is the most likely FRU.
Replace the indicated memory module. In Example 5–3 the most likely FRU is
indicated as memory module #2, slot 3.
The OpenVMS error handler will mark each page bad and attempt page
replacement, indicated in SYSTAT (
). The DCL command SHOW MEMORY
(Example 5–4) will also indicate the result of the OpenVMS operating system
page replacement.
Uncorrectable memory errors will increment the OpenVMS global counter,
which can be viewed using the DCL command SHOW ERROR.
Note
If register MESR <11> was set equal to 1, but MESR <19:12> syndrome
equals 07, no memory subpacket will be logged as a result of incorrect
check bits written to memory because of an NDAL bus parity error
detected by the NMC. In short, this indicates a problem with the CPU
module, not memory. There should be a previous entry with MESR
<22>, NDAL Data Parity Error set equal to 1.
Note
One type of uncorrectable ECC error, that due to a ‘‘disown write’’,
will result in a CRD entry like those for correctable ECC errors.
The FOOTPRINT longword for this entry contains the message
‘‘Uncorrectable ECC errors due to disown write’’. The failing module
should be replaced for this error.
5–20 System Troubleshooting and Diagnostics
