On Wed, Mar 1, 2017 at 12:23 AM, Dickson, Matt MR <[email protected]> wrote: > UNOFFICIAL > > Thanks for that Keith, > > That's got it working again. As for the cause, I had an error in the logs > stating a tablet was hosted and assigned. I've always removed the referenced > tablet in the metadata table to fix this and had no issues in the past. It > looks like I fat fingered the deletion which removed the wrong entry so not > an issue with Accumulo.
Hosted and assigned, that's not good. What version of Accumulo are you running? Do you have any ideas on what may cause this? How often do you see this? Is there any event that usually precedes this? > > Thanks. > > -----Original Message----- > From: Keith Turner [mailto:[email protected]] > Sent: Wednesday, 1 March 2017 03:36 > To: [email protected] > Subject: Re: Fix "Table x has a hole" [SEC=UNOFFICIAL] > > Below are some commands that show how to recreate this problem and how > to fix it. Each table in the metadata table has a pointer to the > previous tablets. Adding and removing splits to a table changes this. > > root@uno> createtable test > > Get the tables ID below we will need it later. > > root@uno test> tables -l > accumulo.metadata => !0 > accumulo.replication => +rep > accumulo.root => +r > test => 3 > trace => 1 > > Add some splits and then scan the metadata table. The pointers to the > previous tablet are in the ~tab:~pr column. The scan below uses the table id > above. > > root@uno test> addsplits 11111111 3333333 > root@uno test> scan -t accumulo.metadata -c ~tab:~pr -b 3; -e 3< > 3;11111111 ~tab:~pr [] \x00 > 3;3333333 ~tab:~pr [] \x0111111111 > 3< ~tab:~pr [] \x013333333 > > Add another split and rescan the metadata table. > > root@uno test> addsplits 2222222 > root@uno test> scan -t accumulo.metadata -c ~tab:~pr -b 3; -e 3< > 3;11111111 ~tab:~pr [] \x00 > 3;2222222 ~tab:~pr [] \x0111111111 > 3;3333333 ~tab:~pr [] \x012222222 > 3< ~tab:~pr [] \x013333333 > > Grant permission to write to the metadata table and then recreate the problem > you have. > > root@uno test> grant Table.WRITE -u root -t accumulo.metadata > root@uno test> table accumulo.metadata > root@uno accumulo.metadata> insert 3;3333333 ~tab ~pr \x0111111111 > root@uno accumulo.metadata> scan -t accumulo.metadata -c ~tab:~pr -b 3; -e > 3< > 3;11111111 ~tab:~pr [] \x00 > 3;2222222 ~tab:~pr [] \x0111111111 > 3;3333333 ~tab:~pr [] \x0111111111 > 3< ~tab:~pr [] \x013333333 > > If you ran check for metadata problems here, should see the error message you > saw. Below, the pointer is fixed and write permission is revoked (to prevent > accidental writes in the future). > > root@uno accumulo.metadata> insert 3;3333333 ~tab ~pr \x012222222 > root@uno accumulo.metadata> revoke Table.WRITE -u root -t accumulo.metadata > root@uno accumulo.metadata> > > After running the command above to fix the potiner, check for metadata > problems should be happy. > > It would be nice to try to track down the cause of this. Spliting a tablet > involves three metadata operations. For fault tolerance, the columns > ~tab:oldprevrow and ~tab:splitRatio are temporarily written. > If a tablet server dies in the middle of splitting a tablet, then Accumulo > will see these temporary columns and attempt to continue the split. So I am > curious if you see these columns? > > On Sun, Feb 26, 2017 at 6:49 PM, Dickson, Matt MR > <[email protected]> wrote: >> UNOFFICIAL >> >> Running the CheckForMetadataProblems on Accumulo is listing >> >> Table xxx has a hole 11111111 != 2222222 >> >> Is there a correct way to repair this? >> >> Thanks in advance.
