Qmail authentication error: Input/output error

[fossxplorer]

I've started to get " imap4: ERR: authentication error: Input/output errorr", any idea whyi get the errors?

[MRatWork]

Inform where this message came from.

[fossxplorer]

from /var/log/maillog

[MRatWork]

Update your system with 'yum clean all; yum update -y; sh /script/cleanup'.

[fossxplorer]

Did that, but still problems with very high server load.
DB log shows some alarming stuff:

OS WAIT ARRAY INFO: reservation count 455
OS WAIT ARRAY INFO: signal count 377
Mutex spin waits 401, rounds 7269, OS waits 227
RW-shared spins 180, rounds 5329, OS waits 174
RW-excl spins 27, rounds 1685, OS waits 54
Spin rounds per wait: 18.13 mutex, 29.61 RW-shared, 62.41 RW-excl
------------
TRANSACTIONS
------------
Trx id counter 8728139
Purge done for trx's n:o < 8728139 undo n:o < 0 state: running but idle
History list length 982
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 8728135, not started
MySQL thread id 849, OS thread handle 0x7f68cf1b9700, query id 8809 localhost vpopmail cleaning up
---TRANSACTION 8728137, not started
MySQL thread id 848, OS thread handle 0x7f68cf401700, query id 8812 localhost vpopmail cleaning up
---TRANSACTION 8728115, not started
MySQL thread id 846, OS thread handle 0x7f68d17b6700, query id 8761 localhost vpopmail cleaning up
---TRANSACTION 8728113, not started
MySQL thread id 843, OS thread handle 0x7f68cf24b700, query id 8749 localhost vpopmail cleaning up
---TRANSACTION 8728111, not started
MySQL thread id 842, OS thread handle 0x7f68cf649700, query id 8746 localhost vpopmail cleaning up
---TRANSACTION 8728109, not started
MySQL thread id 840, OS thread handle 0x7f68d1525700, query id 8739 localhost vpopmail cleaning up
---TRANSACTION 8728107, not started
MySQL thread id 839, OS thread handle 0x7f68d17ff700, query id 8736 localhost vpopmail cleaning up
---TRANSACTION 8728105, not started
MySQL thread id 837, OS thread handle 0x7f68cf6db700, query id 8729 localhost vpopmail cleaning up
---TRANSACTION 8728128, not started
MySQL thread id 836, OS thread handle 0x7f68d15b7700, query id 8795 localhost vpopmail cleaning up
---TRANSACTION 8728103, not started
MySQL thread id 830, OS thread handle 0x7f68d1692700, query id 8726 localhost vpopmail cleaning up
---TRANSACTION 8728133, not started
MySQL thread id 829, OS thread handle 0x7f68cf56e700, query id 8807 localhost vpopmail cleaning up
---TRANSACTION 8728121, not started
MySQL thread id 827, OS thread handle 0x7f68cf525700, query id 8777 localhost vpopmail cleaning up
---TRANSACTION 8728101, not started
MySQL thread id 822, OS thread handle 0x7f68d1724700, query id 8724 localhost vpopmail cleaning up
---TRANSACTION 8728127, not started
MySQL thread id 821, OS thread handle 0x7f68cf76d700, query id 8793 localhost vpopmail cleaning up
---TRANSACTION 8728131, not started
MySQL thread id 820, OS thread handle 0x7f68d1525700, query id 8801 localhost vpopmail cleaning up
FILE I/O
--------
I/O thread 0 state: waiting for i/o request (insert buffer thread)
I/O thread 1 state: waiting for i/o request (log thread)
I/O thread 2 state: waiting for i/o request (read thread)
I/O thread 3 state: waiting for i/o request (read thread)
I/O thread 4 state: waiting for i/o request (read thread)
I/O thread 5 state: waiting for i/o request (read thread)
I/O thread 6 state: waiting for i/o request (write thread)
I/O thread 7 state: waiting for i/o request (write thread)
I/O thread 8 state: waiting for i/o request (write thread)
I/O thread 9 state: waiting for i/o request (write thread)
Pending normal aio reads: 0 [0, 0, 0, 0] , aio writes: 0 [0, 0, 0, 0] ,
 ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0
Pending flushes (fsync) log: 0; buffer pool: 0
7009 OS file reads, 2517 OS file writes, 557 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 2.95 writes/s, 0.90 fsyncs/s

This happens every 15-30 minutes or so.
What's going on?

[MRatWork]

Need optimize mysql. Install mysqltuner with 'yum install mysqltuner -y' and then run it.

[fossxplorer]

It's just hanging [--] Status: -Archive -BDB -Federated -InnoDB -ISAM -NDBCluster .
I had to interrupt as it slow down the whole system.

But why does the database 'kloxo' still use MyISAM tables?
I converted all to InnoDB a while ago, but still i see .MYD and MYI tables under /var/lib/mysql/kloxo/.
E.g 'show CREATE TABLE IF NOT EXISTS web;' shows ..'
 ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
This is wrong as the tables are still on MyISAM.

[MRatWork]

Don't care about storage-engine (myisam, innodb, aria, tokudb), file extensions always .MYD, .MYI and .frm.

[fossxplorer]

Ok.
Looking at CSF logs it seems there are many port flooding on port 25 and 587.
Is there a way to rate limit incoming for these ports using Qmail?

[MRatWork]

Ok.
Looking at CSF logs it seems there are many port flooding on port 25 and 587.
Is there a way to rate limit incoming for these ports using Qmail?

Smtp and submission always need username and password to use this feature. Use CSF is useless for smtp and submission port.

[fossxplorer]

So it's better to create a rule to block when auth for smtp/submission fails after certain counts e.g when i see the following in the maillog:
smtp: 25035 > 535 authentication failed (#5.7.1)?

Ok.
Looking at CSF logs it seems there are many port flooding on port 25 and 587.
Is there a way to rate limit incoming for these ports using Qmail?

Smtp and submission always need username and password to use this feature. Use CSF is useless for smtp and submission port.

[MRatWork]

Yes, better use rule.

[fossxplorer]

The problem is still there:
MySQL thread id 848, OS thread handle 0x7f68cf5b7700, query id 8765 localhost vpopmail cleaning up
---TRANSACTION 8728115, not started
MySQL thread id 846, OS thread handle 0x7f68d17b6700, query id 8761 localhost vpopmail cleaning up
---TRANSACTION 0, not started
MySQL thread id 845, OS thread handle 0x7f68d1649700, query id 8758 localhost vpopmail cleaning up
---TRANSACTION 8728113, not started
MySQL thread id 843, OS thread handle 0x7f68cf24b700, query id 8749 localhost vpopmail cleaning up
---TRANSACTION 8728111, not started
MySQL thread id 842, OS thread handle 0x7f68cf649700, query id 8746 localhost vpopmail cleaning up
---TRANSACTION 8728109, not started
MySQL thread id 840, OS thread handle 0x7f68d1525700, query id 8739 localhost vpopmail cleaning up
---TRANSACTION 8728107, not started
MySQL thread id 839, OS thread handle 0x7f68d17ff700, query id 8736 localhost vpopmail cleaning up
---TRANSACTION 8728105, not started
MySQL thread id 837, OS thread handle 0x7f68cf6db700, query id 8729 localhost vpopmail cleaning up
---TRANSACTION 8728128, not started flushing log

Is the a problem is Maria tuning?

[MRatWork]

MariaDb is backward compatible with MySQL. Use mysqltuner for tuning (remember, config file for MariaDB is /etc/my.cnf.d/server.cnf or MariaDB is /etc/my.cnf.d/my.cnf instead /etc/my.cnf.

[fossxplorer]

Yes, i've optimized it a while back and still issues.
It seems the problem is probably MyISAM tables and locking issues.
There are too many DBs with MyISAM storage engine. Now i need to start converting to InnoDB.
Why is 'kloxo' using MyISAM? Is it safe to convert kloxo's  to tables to InnoDB?