http error 502, mailbox not running

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andreass777
Posts: 1
Joined: Sun Dec 04, 2022 7:27 am

http error 502, mailbox not running

Post by andreass777 »

Hi guys,

some days ago I updated ZCS to this version. We're on a single server installation.

Release 9.0.0.GA.3924.UBUNTU18.64 UBUNTU18_64 NETWORK edition, Patch 9.0.0_P28.

Last update is some months ago. However patches are cumulative, so this should not be a problem.... I thought.

After update, when browsing webapp, I get:

HTTP ERROR 502
Problem accessing ZCS upstream server. Cannot connect to the ZCS upstream server. Connection is refused.
Possible reasons:

upstream server is unreachable
upstream server is currently being upgraded
upstream server is down
Please contact your ZCS administrator to fix the problem.

Powered by Nginx-Zimbra://


I found, that smmailboxdctl is not running.

zimbra@mail:~$ zmcontrol status
Host mail.envicare.at
amavis Running
antispam Running
antivirus Running
convertd Running
dnscache Running
ldap Running
logger Running
mailbox Stopped
zmmailboxdctl is not running.

memcached Running
mta Running
opendkim Running
proxy Running
service webapp Stopped
zmmailboxdctl is not running.

snmp Running
spell Running
stats Running
zimbra webapp Stopped
zmmailboxdctl is not running.
zimbraAdmin webapp Stopped
zmmailboxdctl is not running.

zimlet webapp Stopped
zmmailboxdctl is not running.

zmconfigd Running


In zimbra.log I found this, what makes me worry:

mail postfix/lmtp[26637]: connect to mail.domain.at[192.168.0.124]:7025: Connection refused
mail postfix/lmtp[26637]: C90AFD50884: to=<admin@mail.domain.at>, relay=none, delay=0.07, delays=0.02/0.05/0/0, dsn=4.4.1, status=deferred (connect to mail.domain.at[192.168.0.124]:7025: Connection refused)


nginx.log shows:

2022/12/04 12:05:00 [notice] 30283#0: Using 32KiB of shared memory for upstream_fair
2022/12/04 12:05:00 [notice] 30283#0: using the "epoll" event method
2022/12/04 12:05:00 [notice] 30283#0: nginx/1.20.0
2022/12/04 12:05:00 [notice] 30283#0: OS: Linux 4.15.0-197-generic
2022/12/04 12:05:00 [notice] 30283#0: getrlimit(RLIMIT_NOFILE): 524288:524288
2022/12/04 12:05:00 [notice] 30284#0: start worker processes
2022/12/04 12:05:00 [notice] 30284#0: start worker process 30286
2022/12/04 12:05:00 [notice] 30284#0: start worker process 30287
2022/12/04 12:05:00 [notice] 30284#0: start worker process 30288
2022/12/04 12:05:00 [notice] 30284#0: start worker process 30289
2022/12/04 12:05:00 [info] 30289#0: memcache: 1/1 connections initialized
2022/12/04 12:05:00 [info] 30288#0: memcache: 1/1 connections initialized
2022/12/04 12:05:00 [info] 30287#0: memcache: 1/1 connections initialized
2022/12/04 12:05:00 [info] 30286#0: memcache: 1/1 connections initialized
2022/12/04 12:11:19 [info] 30289#0: *5 SSL_do_handshake() failed (SSL: error:14094416:SSL routines:ssl3_read_bytes:sslv3 alert certificate unknown:SSL alert number 46) while SSL handshaking, client: 192.168.10.150, server: 0.0.0.0:443
2022/12/04 12:11:19 [error] 30289#0: *6 connect() failed (111: Connection refused) while connecting to upstream, client: 192.168.10.150, server: mail.domain.at, request: "GET / HTTP/2.0", upstream: "https://192.168.0.124:8443/", host: "mail.domain.at"
2022/12/04 12:11:19 [error] 30289#0: *6 connect() failed (111: Connection refused) while connecting to upstream, client: 192.168.10.150, server: mail.domain.at, request: "GET / HTTP/2.0", upstream: "https://192.168.0.124:8443/", host: "mail.domain.at"
2022/12/04 12:11:19 [error] 30289#0: *6 connect() failed (111: Connection refused) while connecting to upstream, client: 192.168.10.150, server: mail.domain.at, request: "GET /favicon.ico HTTP/2.0", upstream: "https://192.168.0.124:8443/favicon.ico", host: "mail.domain.at", referrer: "https://mail.domain.at/"


In zmmailboxd.out I can find this part...

Usage: java -jar $JETTY_HOME/start.jar [options] [properties] [configs]
java -jar $JETTY_HOME/start.jar --help # for more information
[0.003s][info][gc] Using G1
OpenJDK 64-Bit Server VM warning: .hotspot_compiler file is present but has been ignored. Run with -XX:CompileCommandFile=.hotspot_compiler to load the file.
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
JettyMonitor monitoring thread pool QueuedThreadPool[qtp891095110]@351d0846{STOPPED,10<=0<=250,i=0,r=-1,q=0}[NO_TRY]
Zimbra server reserving server socket port=7995 bindaddr=null ssl=false
Zimbra server reserving server socket port=7143 bindaddr=null ssl=false
Zimbra server reserving server socket port=7993 bindaddr=null ssl=false
Zimbra server reserving server socket port=7025 bindaddr=null ssl=false



So I updated keystore as descriped here: https://wiki.zimbra.com/wiki/Error_when ... x_services

However, after zmcontrol restart zmmailboxdctl still not running :cry:

What else can I check? Or how should I proceed?

Thanks for answers.
nikhil.d
Zimbra Employee
Zimbra Employee
Posts: 9
Joined: Tue Mar 28, 2023 12:40 pm

Re: http error 502, mailbox not running

Post by nikhil.d »

It looks like proxy service is not able to talk to the mailbox service.
Please have a look at https://wiki.zimbra.com/wiki/Zimbra_Proxy_Guide.

Please run :
zmprov gcf zimbraMailProxyMaxFails
- If the output comes as : zimbraMailProxyMaxFails: 1 , then run below command:
zmprov mcf zimbraMailProxyMaxFails 0

Run zmproxyctl restart and check if issue still persists.
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