Re: pg_rewind success even though getting error 'record with incorrect prev-link'

Ron <ronljohnsonjr@xxxxxxxxx> · Wed, 30 Jan 2019 00:02:35 -0600



    On 1/29/19 9:57 PM, Abdullah Al Maruf wrote:

    
        Hi Michael
          

          > This is pointing out to the end of WAL for the
            current timeline.  You

            > may face it after reading a WAL segment in an area
            which has been used

            > in the past for a recycled segment.

          
          Are you talking about error ` LOG:  invalid record length at
              0/B000098: wanted 24, got 0` ? 
          or,
           `LOG:  record with incorrect
              prev-link 10000/21B0000 at 0/B000098`
          

          Actually, the 1st error is not making any issue. This
            node starts to streaming from primary successfully. 
          But when the second error comes, It appears every 5
            seconds. And, the node is not streaming from master. 
          

            pg_rewind still resolves timeline conflict, but it's
              not fixing this second error.
            

            Any work around?? 
          
          ----------------
          My scenario, in short, I have 1 master nodes (0th node) and three standby nodes (1st,
          
            2nd & 3rd node). When I make the 3rd node as master (by trigger file) and
restarts 0th node as a replica, It shows no problem.
            

            But when both nodes are offline and our leader selection chooses the 0th node
as a master, and tries to reattach the 3rd node as Replica, It throws an
error similar to:
            

            ```
LOG:  invalid record length at 0/B000098: wanted 24, got 0
LOG:  started streaming WAL from primary at 0/B000000 on timeline 2
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
FATAL:  terminating walreceiver process due to administrator command
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098
LOG:  record with incorrect prev-link 10000/21B0000 at 0/B000098

            
    The only error I see is when you apparently manually kill
    the process.  The LOG messages aren't actually errors.

    
    -- 

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