Fatal: master: service(imap): child 20258 killed with signal 6 (core not dumped - set service imap { drop_priv_before_exec=yes })

CJ Keist cj.keist at colostate.edu
Thu Jul 10 19:59:28 UTC 2014 

Update: I had to fall back to the 1.2.17 dovecot code.  Doing that 
solved the invalid user settings and dovecot inability to auto detect 
between mbox and Maildir format for user accounts and no longer have the 
limited number of imap processes either.

Not sure what I was missing in the config files, but this is the route I 
will stay on for now. If it helps here is the 1.2.17 config:

root at mail2:/userM/mail-services/dovecot2/sbin# ./dovecot -n
# 1.2.17: /userM/mail-services/dovecot2/etc/dovecot.conf
Warning: fd limit 256 is lower than what Dovecot can use under full load 
(more than 3072). Either grow the limit or change 
login_max_processes_count and max_mail_processes settings
# OS: SunOS 5.11 i86pc
base_dir: /userM/mail-services/dovecot2/var/run/dovecot/
protocols: imap imaps pop3 pop3s
ssl_cert_file: /userM/mail-services/dovecot2/etc/ssl/dovecot.pem
ssl_key_file: /userM/mail-services/dovecot2/etc/ssl/privkey.pem
ssl_parameters_regenerate: 0
ssl_cipher_list: MEDIUM:!LOW
disable_plaintext_auth: no
login_dir: /userM/mail-services/dovecot2/var/run/dovecot/login
login_executable(default): 
/userM/mail-services/dovecot2/libexec/dovecot/imap-login
login_executable(imap): 
/userM/mail-services/dovecot2/libexec/dovecot/imap-login
login_executable(pop3): 
/userM/mail-services/dovecot2/libexec/dovecot/pop3-login
login_greeting: Cyrus ready.
login_max_processes_count: 1024
max_mail_processes: 1024
mail_debug: yes
mmap_disable: yes
mail_nfs_index: yes
mbox_write_locks: fcntl dotlock
mbox_dotlock_change_timeout: 60
mail_executable(default): /userM/mail-services/dovecot2/libexec/dovecot/imap
mail_executable(imap): /userM/mail-services/dovecot2/libexec/dovecot/imap
mail_executable(pop3): /userM/mail-services/dovecot2/libexec/dovecot/pop3
mail_plugin_dir(default): /userM/mail-services/dovecot2/lib/dovecot/imap
mail_plugin_dir(imap): /userM/mail-services/dovecot2/lib/dovecot/imap
mail_plugin_dir(pop3): /userM/mail-services/dovecot2/lib/dovecot/pop3
lda:
   postmaster_address: cjay at engr.colostate.edu
   hostname: mail1.engr.colostate.edu
   mail_plugins: cmusieve
   mail_plugin_dir: /userM/mail-services/dovecot2/lib/dovecot/lda
   sendmail_path: /userM/mail-services/postfix/lib/sendmail
   rejection_reason: Your message to <%t> was automatically rejected:%n%r
auth default:
   mechanisms: plain login
   verbose: yes
   debug: yes
   worker_max_count: 1024
   passdb:
     driver: pam
   passdb:
     driver: passwd
     args: blocking=yes
   userdb:
     driver: passwd
     args: blocking=yes
   socket:
     type: listen
     client:
       path: /var/lib/postfix/private/auth
       mode: 438
       user: postfix
       group: postfix
     master:
       path: /userM/mail-services/dovecot2/var/run/dovecot//auth-master
       mode: 384


On 7/10/14, 1:11 PM, CJ Keist wrote:
> That didn't work. Still seem to stop accepting new imap connections when
> we hit around 500 processes.
>
>
> On 7/10/14, 12:48 PM, Urban Loesch wrote:
>> Hi,
>>
>> not shure if that helps.
>>
>> In 10-master.conf file exists a "service imap { ... }" section.
>> You could try to increase the "process_limit = " parameter in it.
>>
>> On one of oour servers there we have "process_limit = 2048" and we habe
>> about 1200 concurrent connections without problems.
>>
>> Best,
>> Urban
>>
>>
>> Am 10.07.2014 20:33, schrieb CJ Keist:
>>> It's not fixed. Now the limit looks to be around 500 processes and we
>>> start to get number of connections exceeded.  Any ideas?
>>>
>>>
>>>
>>> On 7/10/14, 10:35 AM, CJ Keist wrote:
>>>> I fixed this issue about the process limit in the 10-master.conf file:
>>>>
>>>> default_process_limit = 5000
>>>> default_client_limit = 30000
>>>>
>>>>
>>>> On 7/10/14, 10:03 AM, CJ Keist wrote:
>>>>> It looks like on the system that once we hit around 200 imap processes
>>>>> it stops there and no more imap processes can be created.  Is there a
>>>>> number of max imap processes in the config file somewhere.  By the way
>>>>> running on OmniOS:
>>>>>
>>>>> SunOS mail2 5.11 omnios-6de5e81 i86pc i386 i86pc
>>>>>
>>>>>
>>>>>
>>>>> On 7/10/14, 9:50 AM, CJ Keist wrote:
>>>>>> Thanks for the reply. I have seen threads about setting the
>>>>>> mail_max_userip_connections, I have set this to 5000 and still people
>>>>>> getting the exceeding connections errorl
>>>>>>
>>>>>>
>>>>>> root at mail2:/userM/mail-services/dovecot/sbin# ./dovecot -n
>>>>>> # 2.2.13: /userM/mail-services/dovecot/etc/dovecot/dovecot.conf
>>>>>> # OS: SunOS 5.11 i86pc
>>>>>> auth_failure_delay = 5 secs
>>>>>> auth_mechanisms = plain login cram-md5
>>>>>> auth_worker_max_count = 3000
>>>>>> base_dir = /userM/mail-services/dovecot/var/run/dovecot/
>>>>>> disable_plaintext_auth = no
>>>>>> hostname = mail2.engr.colostate.edu
>>>>>> managesieve_notify_capability = mailto
>>>>>> managesieve_sieve_capability = fileinto reject envelope
>>>>>> encoded-character vacation subaddress comparator-i;ascii-numeric
>>>>>> relational regex imap4flags copy include variables body enotify
>>>>>> environment mailbox date ihave duplicate
>>>>>> namespace inbox {
>>>>>>    inbox = yes
>>>>>>    location =
>>>>>>    mailbox Drafts {
>>>>>>      special_use = \Drafts
>>>>>>    }
>>>>>>    mailbox Junk {
>>>>>>      special_use = \Junk
>>>>>>    }
>>>>>>    mailbox Sent {
>>>>>>      special_use = \Sent
>>>>>>    }
>>>>>>    mailbox "Sent Messages" {
>>>>>>      special_use = \Sent
>>>>>>    }
>>>>>>    mailbox Trash {
>>>>>>      special_use = \Trash
>>>>>>    }
>>>>>>    prefix =
>>>>>> }
>>>>>> passdb {
>>>>>>    driver = pam
>>>>>> }
>>>>>> passdb {
>>>>>>    driver = passwd
>>>>>> }
>>>>>> postmaster_address = cjay at engr.colostate.edu
>>>>>> service auth {
>>>>>>    unix_listener /var/lib/postfix/private/auth {
>>>>>>      mode = 0666
>>>>>>    }
>>>>>>    unix_listener auth-userdb {
>>>>>>      group = postfix
>>>>>>      mode = 0666
>>>>>>      user = postfix
>>>>>>    }
>>>>>>    user = root
>>>>>> }
>>>>>> service imap-login {
>>>>>>    inet_listener imap {
>>>>>>      port = 143
>>>>>>    }
>>>>>>    inet_listener imaps {
>>>>>>      port = 993
>>>>>>      ssl = yes
>>>>>>    }
>>>>>> }
>>>>>> service pop3-login {
>>>>>>    inet_listener pop3 {
>>>>>>      port = 110
>>>>>>    }
>>>>>>    inet_listener pop3s {
>>>>>>      port = 995
>>>>>>      ssl = yes
>>>>>>    }
>>>>>> }
>>>>>> ssl_cert = </userM/mail-services/dovecot/etc/ssl/dovecot.pem
>>>>>> ssl_key = </userM/mail-services/dovecot/etc/ssl/privkey.pem
>>>>>> userdb {
>>>>>>    args = blocking=yes
>>>>>>    driver = passwd
>>>>>> }
>>>>>> protocol imap {
>>>>>>    mail_max_userip_connections = 5000
>>>>>> }
>>>>>> protocol lda {
>>>>>>    mail_plugins = sieve
>>>>>> }
>>>>>>
>>>>>>
>>>>>> On 7/10/14, 9:45 AM, Reindl Harald wrote:
>>>>>>>
>>>>>>>
>>>>>>> Am 10.07.2014 17:32, schrieb CJ Keist:
>>>>>>>> Another problem is people are getting error message from their
>>>>>>>> clients stating
>>>>>>>> they have exceeded their number of connections.
>>>>>>>
>>>>>>> mail_max_userip_connections = 50
>>>>>>>
>>>>>>> well, how much folders do the have
>>>>>>>
>>>>>>> keep in mind that fpr IDLE you have one connection per user and
>>>>>>> folder
>>>>>>> 10 users with 10 folders behind the same NAT router are 100
>>>>>>> connections
>>>>>>> from the same IP
>>>>>>>
>>>>>>>> On 7/10/14, 9:09 AM, CJ Keist wrote:
>>>>>>>>> Added info:  These errors seem to come from users using mbox
>>>>>>>>> format.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On 7/10/14, 9:04 AM, CJ Keist wrote:
>>>>>>>>>> All,
>>>>>>>>>>     Just move our mail servers over to a new mail server running
>>>>>>>>>> postfix
>>>>>>>>>> 2.11.1 and dovecot 2.2.13 and getting the subject line errors
>>>>>>>>>> in my
>>>>>>>>>> /var/adm/files.  People are complaining of loosing their
>>>>>>>>>> connections to
>>>>>>>>>> the mail server.
>>>>>>>>>>
>>>>>>>>>> I've been able to google this error but haven't found fix for
>>>>>>>>>> this
>>>>>>>>>> yet.
>>>>>>>>>>    NOt sure where to put the drop-priv option in the config files
>>>>>>>>>> either.
>>>>>>>>>>
>>>>>>>>>> Any suggestions?
>>>>>>>>>>
>>>>>>>>>> Var adm message:
>>>>>>>>>> Jul 10 08:54:29 mail2 dovecot: [ID 583609 mail.crit] imap(chen):
>>>>>>>>>> Fatal:
>>>>>>>>>> master: service(imap): child 20258 killed with signal 6 (core not
>>>>>>>>>> dumped
>>>>>>>>>> - set service imap { drop_priv_before_exec=yes })
>>>>>>>>>>
>>>>>>>>>> Here is config output:
>>>>>>>>>>
>>>>>>>>>> root at mail2:/userM/mail-services/dovecot/sbin# ./dovecot -n
>>>>>>>>>> # 2.2.13: /userM/mail-services/dovecot/etc/dovecot/dovecot.conf
>>>>>>>>>> # OS: SunOS 5.11 i86pc
>>>>>>>>>> auth_failure_delay = 5 secs
>>>>>>>>>> auth_mechanisms = plain login cram-md5
>>>>>>>>>> auth_worker_max_count = 300
>>>>>>>>>> base_dir = /userM/mail-services/dovecot/var/run/dovecot/
>>>>>>>>>> disable_plaintext_auth = no
>>>>>>>>>> hostname = mail2.engr.colostate.edu
>>>>>>>>>> managesieve_notify_capability = mailto
>>>>>>>>>> managesieve_sieve_capability = fileinto reject envelope
>>>>>>>>>> encoded-character vacation subaddress comparator-i;ascii-numeric
>>>>>>>>>> relational regex imap4flags copy include variables body enotify
>>>>>>>>>> environment mailbox date ihave duplicate
>>>>>>>>>> namespace inbox {
>>>>>>>>>>     inbox = yes
>>>>>>>>>>     location =
>>>>>>>>>>     mailbox Drafts {
>>>>>>>>>>       special_use = \Drafts
>>>>>>>>>>     }
>>>>>>>>>>     mailbox Junk {
>>>>>>>>>>       special_use = \Junk
>>>>>>>>>>     }
>>>>>>>>>>     mailbox Sent {
>>>>>>>>>>       special_use = \Sent
>>>>>>>>>>     }
>>>>>>>>>>     mailbox "Sent Messages" {
>>>>>>>>>>       special_use = \Sent
>>>>>>>>>>     }
>>>>>>>>>>     mailbox Trash {
>>>>>>>>>>       special_use = \Trash
>>>>>>>>>>     }
>>>>>>>>>>     prefix =
>>>>>>>>>> }
>>>>>>>>>> passdb {
>>>>>>>>>>     driver = pam
>>>>>>>>>> }
>>>>>>>>>> passdb {
>>>>>>>>>>     driver = passwd
>>>>>>>>>> }
>>>>>>>>>> postmaster_address = cjay at engr.colostate.edu
>>>>>>>>>> service auth {
>>>>>>>>>>     unix_listener /var/lib/postfix/private/auth {
>>>>>>>>>>       mode = 0666
>>>>>>>>>>     }
>>>>>>>>>>     unix_listener auth-userdb {
>>>>>>>>>>       group = postfix
>>>>>>>>>>       mode = 0666
>>>>>>>>>>       user = postfix
>>>>>>>>>>     }
>>>>>>>>>>     user = root
>>>>>>>>>> }
>>>>>>>>>> service imap-login {
>>>>>>>>>>     inet_listener imap {
>>>>>>>>>>       port = 143
>>>>>>>>>>     }
>>>>>>>>>>     inet_listener imaps {
>>>>>>>>>>       port = 993
>>>>>>>>>>       ssl = yes
>>>>>>>>>>     }
>>>>>>>>>> }
>>>>>>>>>> service pop3-login {
>>>>>>>>>>     inet_listener pop3 {
>>>>>>>>>>       port = 110
>>>>>>>>>>     }
>>>>>>>>>>     inet_listener pop3s {
>>>>>>>>>>       port = 995
>>>>>>>>>>       ssl = yes
>>>>>>>>>>     }
>>>>>>>>>> }
>>>>>>>>>> ssl_cert = </userM/mail-services/dovecot/etc/ssl/dovecot.pem
>>>>>>>>>> ssl_key = </userM/mail-services/dovecot/etc/ssl/privkey.pem
>>>>>>>>>> userdb {
>>>>>>>>>>     args = blocking=yes
>>>>>>>>>>     driver = passwd
>>>>>>>>>> }
>>>>>>>>>> protocol imap {
>>>>>>>>>>     mail_max_userip_connections = 50
>>>>>>>>>> }
>>>>>>>>>> protocol lda {
>>>>>>>>>>     mail_plugins = sieve
>>>>>>>>>> }
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>

-- 
C. J. Keist                     Email: cj.keist at colostate.edu
Systems Group Manager           Solaris 10 OS (SAI)
Engineering Network Services    Phone: 970-491-0630
College of Engineering, CSU     Fax:   970-491-5569
Ft. Collins, CO 80523-1301

All I want is a chance to prove 'Money can't buy happiness'

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