I have 4 proxies in 4 different regions of AWS. All 4 running with the same configuration:

Debian 10

Zabbix Proxy 4.4.1

4GB Memory

2vcpu

5 days ago, one of my least "load heavy" proxy died, withe following message every time we would try to start the proxy: failed to fork: [12] Cannot allocate memory

Again, all the other 3 are operating with far more load and the same configuration, hardware wise.

We created a new machine, blank, and reinstalled zabbix proxy. But the problem is happening again, this time with the following message before the memory error:

cannot connect to preprocessing service: Cannot connect to service "preprocessing": [111] Connection refused.

At THIS moment, that is my zabbix proxy configuration:

ProxyMode=0

Server=X.X.X.X

1. ServerPort=10051

Hostname=<myhostnamehere>

1. HostnameItem=system.hostname
2. ListenPort=10051
3. SourceIP=
4. LogType=file

LogFile=/var/log/zabbix/zabbix_proxy.log

LogFileSize=2
DebugLevel=3
EnableRemoteCommands=1:
LogRemoteCommands=1

PidFile=<PID PATH>

SocketDir=/var/run/zabbix

1. DBHost=localhost

DBName=<SQLITE PATH>

DBUser=zabbix

1. DBPassword=
2. DBSocket=
3. DBPort=
4. ProxyLocalBuffer=0
   ProxyOfflineBuffer=1
   HeartbeatFrequency=60
   ConfigFrequency=300
   DataSenderFrequency=5
   StartPollers=25
5. StartIPMIPollers=0
   StartPreprocessors=1
   StartPollersUnreachable=100
   StartTrappers=300
   StartPingers=3
   StartDiscoverers=0
   StartHTTPPollers=5
6. JavaGateway=
7. JavaGatewayPort=10052
8. StartJavaPollers=0
9. StartVMwareCollectors=0

1. VMwareFrequency=60
2. VMwarePerfFrequency=60
3. VMwareCacheSize=8M
4. VMwareTimeout=10
5. SNMPTrapperFile=/tmp/zabbix_traps.tmp

SNMPTrapperFile=<SNMP PATH>

1. StartSNMPTrapper=0
2. ListenIP=0.0.0.0
   HousekeepingFrequency=6
   CacheSize=512M
   StartDBSyncers=5
   HistoryCacheSize=32M
   HistoryIndexCacheSize=8M

Timeout=30

1. TrapperTimeout=300
   UnreachablePeriod=60
   UnavailableDelay=60
2. UnreachableDelay=15
   ExternalScripts=<EXTERNAL SCRIPTS PATH>

FpingLocation=/usr/bin/fping

Fping6Location=/usr/bin/fping6

LogSlowQueries=3000