side issue
if you are getting inconsistant dsyncs there is no real way to fix this in the long run.
i know its a pain (already had to my self)
i needed to do a full sync, take one server offline, delete the user dir (with dovecot offline) and then rsync (or somehow duplicate the main server's user data) over the the remote again.
then bring remote back up and it kind or worked worked
best suggestion is to bring the main server down at night so the copy is clean?
if using postfix you can enable the soft bounce option and the mail will back spool until everything comes back online
(needs to be enable on bother servers)
replication was still an issue on accounts with 300+ folders in them, still working on a fix for that.
Happy Tuesday !!! Thanks - paul
Paul Kudla
Scom.ca Internet Services http://www.scom.ca 004-1009 Byron Street South Whitby, Ontario - Canada L1N 4S3
Toronto 416.642.7266 Main 1.866.411.7266 Fax 1.888.892.7266
On 4/25/2022 10:01 AM, Arnaud Abélard wrote:
Ah, I'm now getting errors in the logs, that would explains the increasing number of failed sync requests:
dovecot: imap(xxxxx)<2961235><Bs6w43rdQPAqAcsFiXEmAInUhhA3Rfqh>: Error: Mailbox INBOX: /vmail/l/i/xxxxx/dovecot.index reset, view is now inconsistent
And sure enough:
# dovecot replicator status xxxxx
xxxxx none 00:02:54 07:11:28 - y
What could explain that error?
Arnaud
On 25/04/2022 15:13, Arnaud Abélard wrote:
Hello,
On my side we are running Linux (Debian Buster).
I'm not sure my problem is actually the same as Paul or you Sebastian since I have a lot of boxes but those are actually small (quota of 110MB) so I doubt any of them have more than a dozen imap folders.
The main symptom is that I have tons of full sync requests awaiting but even though no other sync is pending the replicator just waits for something to trigger those syncs.
Today, with users back I can see that normal and incremental syncs are being done on the 15 connections, with an occasional full sync here or there and lots of "Waiting 'failed' requests":
Queued 'sync' requests 0
Queued 'high' requests 0
Queued 'low' requests 0
Queued 'failed' requests 122
Queued 'full resync' requests 28785
Waiting 'failed' requests 4294
Total number of known users 42512
So, why didn't the replicator take advantage of the weekend to replicate the mailboxes while no user were using them?
Arnaud
On 25/04/2022 13:54, Sebastian Marske wrote:
Hi there,
thanks for your insights and for diving deeper into this Paul!
For me, the users ending up in 'Waiting for dsync to finish' all have more than 256 Imap folders as well (ranging from 288 up to >5500; as per 'doveadm mailbox list -u <username> | wc -l'). For more details on my setup please see my post from February [1].
@Arnaud: What OS are you running on?
Best Sebastian
[1] https://dovecot.org/pipermail/dovecot/2022-February/124168.html
On 4/24/22 19:36, Paul Kudla (SCOM.CA Internet Services Inc.) wrote:
Question having similiar replication issues
pls read everything below and advise the folder counts on the non-replicated users?
i find the total number of folders / account seems to be a factor and NOT the size of the mail box
ie i have customers with 40G of emails no problem over 40 or so folders and it works ok
300+ folders seems to be the issue
i have been going through the replication code
no errors being logged
i am assuming that the replication --> dhclient --> other server is timing out or not reading the folder lists correctly (ie dies after X folders read)
thus i am going through the code patching for log entries etc to find the issues.
see
[13:33:57] mail18.scom.ca [root:0] /usr/local/var/lib/dovecot # ll total 86 drwxr-xr-x 2 root wheel uarch 4B Apr 24 11:11 . drwxr-xr-x 4 root wheel uarch 4B Mar 8 2021 .. -rw-r--r-- 1 root wheel uarch 73B Apr 24 11:11 instances -rw-r--r-- 1 root wheel uarch 160K Apr 24 13:33 replicator.db
[13:33:58] mail18.scom.ca [root:0] /usr/local/var/lib/dovecot #
replicator.db seems to get updated ok but never processed properly.
# sync.users nick@elirpa.com high 00:09:41 463:47:01 - y keith@elirpa.com high 00:09:23 463:45:43 - y paul@scom.ca high 00:09:41 463:46:51 - y ed@scom.ca high 00:09:43 463:47:01 - y ed.hanna@dssmgmt.com high 00:09:42 463:46:58 - y paul@paulkudla.net high 00:09:44 463:47:03 580:35:07 y
so ....
two things :
first to get the production stuff to work i had to write a script that whould find the bad sync's and the force a dsync between the servers
i run this every five minutes or each server.
in crontab
*/10 * * * * root /usr/bin/nohup /programs/common/sync.recover > /dev/null
python script to sort things out
# cat /programs/common/sync.recover #!/usr/local/bin/python3
#Force sync between servers that are reporting bad?
import os,sys,django,socket from optparse import OptionParser
from lib import *
#Sample Re-Index MB #doveadm -D force-resync -u paul@scom.ca -f INBOX*
USAGE_TEXT = '''
usage: %%prog %s[options] '''parser = OptionParser(usage=USAGE_TEXT % '', version='0.4')
parser.add_option("-m", "--send_to", dest="send_to", help="Send Email To") parser.add_option("-e", "--email", dest="email_box", help="Box to Index") parser.add_option("-d", "--detail",action='store_true', dest="detail",default =False, help="Detailed report") parser.add_option("-i", "--index",action='store_true', dest="index",default =False, help="Index")
options, args = parser.parse_args()
print (options.email_box) print (options.send_to) print (options.detail)
#sys.exit()
print ('Getting Current User Sync Status') command = commands("/usr/local/bin/doveadm replicator status '*'")
#print command
sync_user_status = command.output.split('\n')
#print sync_user_status
synced = []
for n in range(1,len(sync_user_status)) : user = sync_user_status[n] print ('Processing User : %s' %user.split(' ')[0]) if user.split(' ')[0] != options.email_box : if options.email_box != None : continue
if options.index == True : command = '/usr/local/bin/doveadm -D force-resync -u %s -f INBOX*' %user.split(' ')[0] command = commands(command) command = command.output
#print user for nn in range (len(user)-1,0,-1) : #print nn #print user[nn]
if user[nn] == '-' : #print 'skipping ... %s' %user.split(' ')[0]
break
if user[nn] == 'y': #Found a Bad Mailbox print ('syncing ... %s' %user.split(' ')[0])
if options.detail == True : command = '/usr/local/bin/doveadm -D sync -u %s -d -N -l 30 -U' %user.split(' ')[0] print (command) command = commands(command) command = command.output.split('\n') print (command) print ('Processed Mailbox for ... %s' %user.split(' ')[0] ) synced.append('Processed Mailbox for ... %s' %user.split(' ')[0]) for nnn in range(len(command)): synced.append(command[nnn]
- '\n') break
if options.detail == False : #command = '/usr/local/bin/doveadm -D sync -u %s -d -N -l 30 -U' %user.split(' ')[0] #print (command) #command = os.system(command) command = subprocess.Popen( ["/usr/local/bin/doveadm sync -u %s -d -N -l 30 -U" %user.split(' ')[0] ],
shell = True, stdin=None, stdout=None, stderr=None, close_fds=True)print ( 'Processed Mailbox for ... %s' %user.split(' ')[0] ) synced.append('Processed Mailbox for ... %s' %user.split(' ')[0]) #sys.exit() break
if len(synced) != 0 : #send email showing bad synced boxes ?
if options.send_to != None : send_from = 'monitor@scom.ca' send_to = ['%s' %options.send_to] send_subject = 'Dovecot Bad Sync Report for : %s' %(socket.gethostname()) send_text = '\n\n' for n in range (len(synced)) : send_text = send_text + synced[n] + '\n'
send_files = [] sendmail (send_from, send_to, send_subject, send_text, send_files)
sys.exit()
second :
i posted this a month ago - no response
please appreciate that i am trying to help ....
after much testing i can now reporduce the replication issues at hand
I am running on freebsd 12 & 13 stable (both test and production servers)
sdram drives etc ...
Basically replication works fine until reaching a folder quantity of ~ 256 or more
to reproduce using doveadm i created folders like
INBOX/folder-0 INBOX/folder-1 INBOX/folder-2 INBOX/folder-3 and so forth ......
I created 200 folders and they replicated ok on both servers
I created another 200 (400 total) and the replicator got stuck and would not update the mbox on the alternate server anymore and is still updating 4 days later ?
basically replicator goes so far and either hangs or more likely bails on an error that is not reported to the debug reporting ?
however dsync will sync the two servers but only when run manually (ie all the folders will sync)
I have two test servers avaliable if you need any kind of access - again here to help.
[07:28:42] mail18.scom.ca [root:0] ~ # sync.status Queued 'sync' requests 0 Queued 'high' requests 6 Queued 'low' requests 0 Queued 'failed' requests 0 Queued 'full resync' requests 0 Waiting 'failed' requests 0 Total number of known users 255
username type status paul@scom.ca normal Waiting for dsync to finish keith@elirpa.com incremental Waiting for dsync to finish ed.hanna@dssmgmt.com incremental Waiting for dsync to finish ed@scom.ca incremental Waiting for dsync to finish nick@elirpa.com incremental Waiting for dsync to finish paul@paulkudla.net incremental Waiting for dsync to finish
i have been going through the c code and it seems the replication gets requested ok
replicator.db does get updated ok with the replicated request for the mbox in question.
however i am still looking for the actual replicator function in the lib's that do the actual replication requests
the number of folders & subfolders is defanately the issue - not the mbox pyhsical size as thought origionally.
if someone can point me in the right direction, it seems either the replicator is not picking up on the number of folders to replicat properly or it has a hard set limit like 256 / 512 / 65535 etc and stops the replication request thereafter.
I am mainly a machine code programmer from the 80's and have concentrated on python as of late, 'c' i am starting to go through just to give you a background on my talents.
It took 2 months to finger this out.
this issue also seems to be indirectly causing the duplicate messages supression not to work as well.
python programming to reproduce issue (loops are for last run started @ 200 - fyi) :
# cat mbox.gen #!/usr/local/bin/python2
import os,sys
from lib import *
user = 'paul@paulkudla.net'
""" for count in range (0,600) : box = 'INBOX/folder-%s' %count print count command = '/usr/local/bin/doveadm mailbox create -s -u %s %s' %(user,box) print command a = commands.getoutput(command) print a """
for count in range (0,600) : box = 'INBOX/folder-0/sub-%' %count print count command = '/usr/local/bin/doveadm mailbox create -s -u %s %s' %(user,box) print command a = commands.getoutput(command) print a
#sys.exit()
Happy Sunday !!! Thanks - paul
Paul Kudla
Scom.ca Internet Services http://www.scom.ca 004-1009 Byron Street South Whitby, Ontario - Canada L1N 4S3
Toronto 416.642.7266 Main 1.866.411.7266 Fax 1.888.892.7266
On 4/24/2022 10:22 AM, Arnaud Abélard wrote:
Hello,
I am working on replicating a server (and adding compression on the other side) and since I had "Error: dsync I/O has stalled, no activity for 600 seconds (version not received)" errors I upgraded both source and destination server with the latest 2.3 version (2.3.18). While before the upgrade all the 15 replication connections were busy after upgrading dovecot replicator dsync-status shows that most of the time nothing is being replicated at all. I can see some brief replications that last, but 99,9% of the time nothing is happening at all.
I have a replication_full_sync_interval of 12 hours but I have thousands of users with their last full sync over 90 hours ago.
"doveadm replicator status" also shows that i have over 35,000 queued full resync requests, but no sync, high or low queued requests so why aren't the full requests occuring?
There are no errors in the logs.
Thanks,
Arnaud