Re: Request for Help: BackupPC_refCountUpdate: missing pool file
Ronald Colcernian <[email protected]> Wed, 22 Jul 2026 08:24:18 -0400
| Newsgroups | gmane.comp.sysutils.backup.backuppc.general |
|---|---|
| Message-ID | <CAAb-kPcrn1sRi62E9rPZADQ2ah7FHzqTChvwPD5L_O0hmjZ63g@mail.gmail.com> |
--===============0281127507692861154== Content-Type: multipart/alternative; boundary="000000000000a4bf7106573238de" --000000000000a4bf7106573238de Content-Type: text/plain; charset="UTF-8" Thanks for the help. Found them all in one backup as you predicted. Deleted the backup and they are gone On Sat, Jul 18, 2026, 11:07 G.W. Haywood <[email protected]> wrote: > Hi there, > > On Sat, 18 Jul 2026, Ron Colcernian wrote: > > > > Would someone kindly point me to the remedy for the following message? > > > > What document should I read to guide me to resolution of this issue? > > > > I have 1157 of these messages. > > > > 2026-07-16 01:24:05 admin : BackupPC_refCountUpdate: missing pool > > file 2f168f994f2744a2c4c9046b821ebcc1 count 1 > > > > I don't know how long this has been happening, sadly. > > > > Cpool is V4 (90% of it was converted from V3, 10% is newly created V4 > > daily backups) > > Running backuppc, version 4.4.0 > > Ubuntu 24.04 Instance on a Proxmo install. > > Going through this a bit quickly because of time pressures, I'm sorry > if there are things like typos and repetition which I've seen in some > of my recent posts. :( Also I've generalized it a little - I tend to > do that in case it helps other people later on; I guess you have just > one missing pool file? > > CAUSES: > > Unfortunately there seem to be several causes for missing pool files. > They are mentioned in mailng list threads listed below - the mailing > list archive is a valuable resource. I prefer to download the entire > archive and use 'grep' to search it. > > Here are the causes that I know of, descending order of probability: > > 1. When either the BackupPC server or one of its clients is shut down > improperly while a backup is active. > > 2. Problems when migrating from a V3 pool to a V4 pool. Possibly the > system 'ulimit' may have been too small, but the migration utility has > not been tested well. In view of the numbers of installations and how > often the utility is used, it probably never will be. My experience > with it was unsatisfactory but that was around ten years ago. In the > end for that installation I started from scratch with a fresh V4 taken > from source (the copy which gave trouble was from a Debian package). > > 3. Some older versions of BackupPC 4.x contained faults that sometimes > caused missing pool files. At least to the extent that they are known > those faults have been fixed. Obviously upgrade faulty versions, but > version 4.4.0 should be fine. There are discussions in Github issues > as well as on the mailing list. > > FIXES: > > Fortunately, missing pool files isn't a show-stopper. If you come > across missing pool file messages: > > If they're artifacts of the V3->V4 conversion, then you can probably > just ignore them. The messages will eventually stop when the backups > that reference them expire. If you delete those backups manually the > same thing will happen (but you don't know which they are, read on). > > You can just tell BackupPC to back up the files which are missing from > the pool. It isn't straightforward to get from a pool file hash to > the original file but there are useful pointers in the mail archives. > Below [*] are some threads from the mailing list with more info. Some > are a little old, but no less useful for that. Some refer to scripts > that you might find useful. I see there's a promise of another script > in the not too distant future from Matthias@gmx... (and I'd be pleased > to see it Matthias, whatever state it's in. :) > > If you're using rsync/d for Xfer it might be worth tweaking the rsync > options so that the destination files are compared bytewise instead of > relying on the comparison of the metadata (timestamps and file sizes). > I haven't tried this, and don't know for sure that it will help - I'm > going on the comment in the config.pl file. The tweak I'm thinking of > is --ignore-times in place of --checksum in $Conf{RsyncFullArgsExtra}. > You could instead add this to $Conf{RsyncArgsExtra} so that it would > affect incremental backups as well as fulls, but that might not help > much because the file missing from the pool probably isn't changing on > the client (or it would have been backed up by now anyway) so it won't > be compared until the next full backup happens. > > You might well find that all the missing pool files relate to a single > client. In that case you might just rename the client directory in > /var/lib/Backuppc/pc/[**] to some random string which doesn't resemble > one of your host names. BackupPC will start backups from scratch for > that client. I do that a lot in testing. When you're happy that your > backups are OK, just delete the renamed directory tree. > > HTH > > [*] > https://sourceforge.net/p/backuppc/mailman/message/35708181/ > https://sourceforge.net/p/backuppc/mailman/message/37269343/ > https://sourceforge.net/p/backuppc/mailman/message/58833484/ > https://sourceforge.net/p/backuppc/mailman/message/59127801/ > https://sourceforge.net/p/backuppc/mailman/message/59221642/ > > [**] > Or wherever your /pc/ and /pool/ directories happen to live. > > -- > > 73, > Ged. > > > _______________________________________________ > BackupPC-users mailing list > [email protected] > List: https://lists.sourceforge.net/lists/listinfo/backuppc-users > Wiki: https://github.com/backuppc/backuppc/wiki > Project: https://backuppc.github.io/backuppc/ > --000000000000a4bf7106573238de Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"auto">Thanks for the help. Found them all in one backup as you = predicted. Deleted the backup and they are gone=C2=A0</div><br><div class= =3D"gmail_quote gmail_quote_container"><div dir=3D"ltr" class=3D"gmail_attr= ">On Sat, Jul 18, 2026, 11:07 G.W. Haywood <<a href=3D"mailto:backup@jub= ileegroup.co.uk">[email protected]</a>> wrote:<br></div><blockqu= ote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc s= olid;padding-left:1ex">Hi there,<br> <br> On Sat, 18 Jul 2026, Ron Colcernian wrote:<br> > <br> > Would someone kindly point me to the remedy for the following message?= <br> ><br> > What document should I read to guide me to resolution of this issue?<b= r> ><br> > I have 1157 of these messages.<br> ><br> > 2026-07-16 01:24:05=C2=A0 admin : BackupPC_refCountUpdate: missing poo= l<br> > file 2f168f994f2744a2c4c9046b821ebcc1 count 1<br> ><br> > I don't know how long this has been happening, sadly.<br> ><br> > Cpool is V4 (90% of it was converted from V3, 10% is newly created V4<= br> > daily backups)<br> > Running backuppc, version 4.4.0<br> > Ubuntu 24.04 Instance on a Proxmo install.<br> <br> Going through this a bit quickly because of time pressures, I'm sorry<b= r> if there are things like typos and repetition which I've seen in some<b= r> of my recent posts. :(=C2=A0 Also I've generalized it a little - I tend= to<br> do that in case it helps other people later on; I guess you have just<br> one missing pool file?<br> <br> CAUSES:<br> <br> Unfortunately there seem to be several causes for missing pool files.<br> They are mentioned in mailng list threads listed below - the mailing<br> list archive is a valuable resource.=C2=A0 I prefer to download the entire<= br> archive and use 'grep' to search it.<br> <br> Here are the causes that I know of, descending order of probability:<br> <br> 1. When either the BackupPC server or one of its clients is shut down<br> improperly while a backup is active.<br> <br> 2. Problems when migrating from a V3 pool to a V4 pool.=C2=A0 Possibly the<= br> system 'ulimit' may have been too small, but the migration utility = has<br> not been tested well.=C2=A0 In view of the numbers of installations and how= <br> often the utility is used, it probably never will be.=C2=A0 My experience<b= r> with it was unsatisfactory but that was around ten years ago.=C2=A0 In the<= br> end for that installation I started from scratch with a fresh V4 taken<br> from source (the copy which gave trouble was from a Debian package).<br> <br> 3. Some older versions of BackupPC 4.x contained faults that sometimes<br> caused missing pool files.=C2=A0 At least to the extent that they are known= <br> those faults have been fixed.=C2=A0 Obviously upgrade faulty versions, but<= br> version 4.4.0 should be fine.=C2=A0 There are discussions in Github issues<= br> as well as on the mailing list.<br> <br> FIXES:<br> <br> Fortunately, missing pool files isn't a show-stopper.=C2=A0 If you come= <br> across missing pool file messages:<br> <br> If they're artifacts of the V3->V4 conversion, then you can probably= <br> just ignore them.=C2=A0 The messages will eventually stop when the backups<= br> that reference them expire.=C2=A0 If you delete those backups manually the<= br> same thing will happen (but you don't know which they are, read on).<br= > <br> You can just tell BackupPC to back up the files which are missing from<br> the pool.=C2=A0 It isn't straightforward to get from a pool file hash t= o<br> the original file but there are useful pointers in the mail archives.<br> Below [*] are some threads from the mailing list with more info.=C2=A0 Some= <br> are a little old, but no less useful for that.=C2=A0 Some refer to scripts<= br> that you might find useful.=C2=A0 I see there's a promise of another sc= ript<br> in the not too distant future from Matthias@gmx... (and I'd be pleased<= br> to see it Matthias, whatever state it's in. :)<br> <br> If you're using rsync/d for Xfer it might be worth tweaking the rsync<b= r> options so that the destination files are compared bytewise instead of<br> relying on the comparison of the metadata (timestamps and file sizes).<br> I haven't tried this, and don't know for sure that it will help - I= 'm<br> going on the comment in the <a href=3D"http://config.pl" rel=3D"noreferrer = noreferrer" target=3D"_blank">config.pl</a> file.=C2=A0 The tweak I'm t= hinking of<br> is --ignore-times in place of --checksum in $Conf{RsyncFullArgsExtra}.<br> You could instead add this to $Conf{RsyncArgsExtra} so that it would<br> affect incremental backups as well as fulls, but that might not help<br> much because the file missing from the pool probably isn't changing on<= br> the client (or it would have been backed up by now anyway) so it won't<= br> be compared until the next full backup happens.<br> <br> You might well find that all the missing pool files relate to a single<br> client.=C2=A0 In that case you might just rename the client directory in<br= > /var/lib/Backuppc/pc/[**] to some random string which doesn't resemble<= br> one of your host names.=C2=A0 BackupPC will start backups from scratch for<= br> that client.=C2=A0 I do that a lot in testing.=C2=A0 When you're happy = that your<br> backups are OK, just delete the renamed directory tree.<br> <br> HTH<br> <br> [*]<br> <a href=3D"https://sourceforge.net/p/backuppc/mailman/message/35708181/" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://sourceforge.net/p/bac= kuppc/mailman/message/35708181/</a><br> <a href=3D"https://sourceforge.net/p/backuppc/mailman/message/37269343/" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://sourceforge.net/p/bac= kuppc/mailman/message/37269343/</a><br> <a href=3D"https://sourceforge.net/p/backuppc/mailman/message/58833484/" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://sourceforge.net/p/bac= kuppc/mailman/message/58833484/</a><br> <a href=3D"https://sourceforge.net/p/backuppc/mailman/message/59127801/" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://sourceforge.net/p/bac= kuppc/mailman/message/59127801/</a><br> <a href=3D"https://sourceforge.net/p/backuppc/mailman/message/59221642/" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://sourceforge.net/p/bac= kuppc/mailman/message/59221642/</a><br> <br> [**]<br> Or wherever your /pc/ and /pool/ directories happen to live.<br> <br> -- <br> <br> 73,<br> Ged.<br> <br> <br> _______________________________________________<br> BackupPC-users mailing list<br> <a href=3D"mailto:[email protected]" target=3D"_blank" r= el=3D"noreferrer">[email protected]</a><br> List:=C2=A0 =C2=A0 <a href=3D"https://lists.sourceforge.net/lists/listinfo/= backuppc-users" rel=3D"noreferrer noreferrer" target=3D"_blank">https://lis= ts.sourceforge.net/lists/listinfo/backuppc-users</a><br> Wiki:=C2=A0 =C2=A0 <a href=3D"https://github.com/backuppc/backuppc/wiki" re= l=3D"noreferrer noreferrer" target=3D"_blank">https://github.com/backuppc/b= ackuppc/wiki</a><br> Project: <a href=3D"https://backuppc.github.io/backuppc/" rel=3D"noreferrer= noreferrer" target=3D"_blank">https://backuppc.github.io/backuppc/</a><br> </blockquote></div> --000000000000a4bf7106573238de-- --===============0281127507692861154== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============0281127507692861154== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ BackupPC-users mailing list [email protected] List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: https://github.com/backuppc/backuppc/wiki Project: https://backuppc.github.io/backuppc/ --===============0281127507692861154==--