zabbix web page pending

[walter]

Hi all,

I upgrade Zabbix from 4.2.5 to 4.4.1 using sources. After restarting the Zabbix-server for a little while(sometimes even without any seconds), the web page stays loading, I saw it was pending status on chrome. Once I shut down the server, the page recovered immediately.
There's nothing useful information on logs and it seems the Zabbix server is still worked.
Has anyone encountered this problem?

zabbix status by systemd:
● zabbix-server.service - Cluster Controlled zabbix-server
Loaded: loaded (/usr/lib/systemd/system/zabbix-server.service; disabled; vendor preset: disabled)
Drop-In: /run/systemd/system/zabbix-server.service.d
└─50-pacemaker.conf
Active: active (running) since Thu 2019-11-07 10:31:47 CST; 15min ago
Process: 95962 ExecStart=/usr/local/sbin/zabbix_server -c /usr/local/etc/zabbix_server.conf (code=exited, status=0/SUCCESS)
Main PID: 95964 (zabbix_server)
CGroup: /system.slice/zabbix-server.service
├─95964 /usr/local/sbin/zabbix_server -c /usr/local/etc/zabbix_server.conf
├─96108 /usr/local/sbin/zabbix_server: configuration syncer [synced configuration in 12.505660 sec, idle 300 sec]
├─96109 /usr/local/sbin/zabbix_server: ipmi manager #1 [scheduled 0, polled 0 values, idle 5.005188 sec during 5.005247 sec]
├─96110 /usr/local/sbin/zabbix_server: housekeeper [startup idle for 30 minutes]
├─96111 /usr/local/sbin/zabbix_server: timer #1 [updated 0 hosts, suppressed 0 events in 0.009449 sec, idle 59 sec]
├─96112 /usr/local/sbin/zabbix_server: http poller #1 [got 0 values in 0.002098 sec, idle 5 sec]
├─96113 /usr/local/sbin/zabbix_server: http poller #2 [got 0 values in 0.002434 sec, idle 5 sec]
├─96114 /usr/local/sbin/zabbix_server: http poller #3 [got 0 values in 0.001998 sec, idle 5 sec]
├─96115 /usr/local/sbin/zabbix_server: http poller #4 [got 0 values in 0.002042 sec, idle 5 sec]
├─96116 /usr/local/sbin/zabbix_server: discoverer #1 [processed 0 rules in 0.002147 sec, idle 60 sec]
├─96117 /usr/local/sbin/zabbix_server: discoverer #2 [processed 0 rules in 0.002155 sec, idle 60 sec]
├─96118 /usr/local/sbin/zabbix_server: discoverer #3 [processed 0 rules in 0.001910 sec, idle 60 sec]
├─96119 /usr/local/sbin/zabbix_server: discoverer #4 [processed 0 rules in 0.001980 sec, idle 60 sec]
├─96120 /usr/local/sbin/zabbix_server: discoverer #5 [processed 0 rules in 0.002191 sec, idle 60 sec]
├─96121 /usr/local/sbin/zabbix_server: discoverer #6 [processed 0 rules in 0.002027 sec, idle 60 sec]
├─96122 /usr/local/sbin/zabbix_server: discoverer #7 [processed 0 rules in 0.002100 sec, idle 60 sec]
├─96123 /usr/local/sbin/zabbix_server: discoverer #8 [processed 0 rules in 0.004145 sec, idle 60 sec]
├─96125 /usr/local/sbin/zabbix_server: history syncer #1 [processed 1167 values, 1569 triggers in 0.159645 sec, idle 1 sec]
├─96127 /usr/local/sbin/zabbix_server: history syncer #2 [processed 1709 values, 1848 triggers in 0.159945 sec, idle 1 sec]
├─96129 /usr/local/sbin/zabbix_server: history syncer #3 [processed 1004 values, 1044 triggers in 0.128629 sec, idle 1 sec]
├─96131 /usr/local/sbin/zabbix_server: history syncer #4 [processed 1002 values, 1210 triggers in 0.143770 sec, idle 1 sec]
├─96133 /usr/local/sbin/zabbix_server: escalator #1 [processed 0 escalations in 0.005390 sec, idle 3 sec]
├─96134 /usr/local/sbin/zabbix_server: escalator #2 [processed 0 escalations in 0.005141 sec, idle 3 sec]
├─96135 /usr/local/sbin/zabbix_server: ipmi poller #1 started
├─96136 /usr/local/sbin/zabbix_server: java poller #1 [got 0 values in 0.000016 sec, idle 5 sec]
├─96137 /usr/local/sbin/zabbix_server: java poller #2 [got 0 values in 0.000017 sec, idle 5 sec]
├─96138 /usr/local/sbin/zabbix_server: java poller #3 [got 0 values in 0.000017 sec, idle 5 sec]
├─96139 /usr/local/sbin/zabbix_server: java poller #4 [got 0 values in 0.000010 sec, idle 5 sec]
├─96140 /usr/local/sbin/zabbix_server: java poller #5 [got 0 values in 0.000015 sec, idle 5 sec]
├─96141 /usr/local/sbin/zabbix_server: proxy poller #1 [exchanged data with 0 proxies in 0.000016 sec, idle 5 sec]
├─96142 /usr/local/sbin/zabbix_server: self-monitoring [processed data in 0.000018 sec, idle 1 sec]
├─96143 /usr/local/sbin/zabbix_server: task manager [processed 0 task(s) in 0.001865 sec, idle 5 sec]
├─96145 /usr/local/sbin/zabbix_server: poller #1 [got 68 values in 0.084686 sec, getting values]
├─96146 /usr/local/sbin/zabbix_server: poller #2 [got 547 values in 3.178219 sec, getting values]
├─96148 /usr/local/sbin/zabbix_server: poller #3 [got 414 values in 2.268457 sec, getting values]
├─96150 /usr/local/sbin/zabbix_server: poller #4 [got 0 values in 0.000013 sec, getting values]
├─96152 /usr/local/sbin/zabbix_server: poller #5 [got 591 values in 2.257468 sec, getting values]
├─96154 /usr/local/sbin/zabbix_server: poller #6 [got 0 values in 0.000015 sec, idle 1 sec]
├─96156 /usr/local/sbin/zabbix_server: poller #7 [got 0 values in 0.000010 sec, idle 1 sec]
├─96158 /usr/local/sbin/zabbix_server: poller #8 [got 794 values in 3.621533 sec, getting values]
├─96159 /usr/local/sbin/zabbix_server: poller #9 [got 215 values in 0.785173 sec, idle 1 sec]
├─96160 /usr/local/sbin/zabbix_server: poller #10 [got 227 values in 0.275362 sec, getting values]
├─96161 /usr/local/sbin/zabbix_server: poller #11 [got 0 values in 0.000358 sec, idle 1 sec]
├─96162 /usr/local/sbin/zabbix_server: poller #12 [got 80 values in 1.128298 sec, idle 1 sec]
├─96163 /usr/local/sbin/zabbix_server: poller #13 [got 643 values in 3.916924 sec, idle 1 sec]
├─96164 /usr/local/sbin/zabbix_server: poller #14 [got 68 values in 0.062413 sec, getting values]
├─96165 /usr/local/sbin/zabbix_server: poller #15 [got 331 values in 1.138657 sec, idle 1 sec]
├─96166 /usr/local/sbin/zabbix_server: poller #16 [got 162 values in 0.954815 sec, getting values]
├─96167 /usr/local/sbin/zabbix_server: poller #17 [got 420 values in 3.222932 sec, getting values]
├─96168 /usr/local/sbin/zabbix_server: poller #18 [got 68 values in 0.093703 sec, getting values]
├─96169 /usr/local/sbin/zabbix_server: poller #19 [got 56 values in 0.067309 sec, idle 1 sec]
├─96170 /usr/local/sbin/zabbix_server: poller #20 [got 354 values in 0.969579 sec, getting values]
├─96171 /usr/local/sbin/zabbix_server: poller #21 [got 221 values in 0.869439 sec, getting values]
├─96172 /usr/local/sbin/zabbix_server: poller #22 [got 619 values in 3.669808 sec, getting values]
├─96173 /usr/local/sbin/zabbix_server: poller #23 [got 68 values in 0.093960 sec, getting values]
├─96174 /usr/local/sbin/zabbix_server: poller #24 [got 151 values in 0.935967 sec, getting values]
├─96175 /usr/local/sbin/zabbix_server: poller #25 [got 235 values in 0.889282 sec, getting values]
├─96176 /usr/local/sbin/zabbix_server: poller #26 [got 63 values in 0.053715 sec, idle 1 sec]
├─96177 /usr/local/sbin/zabbix_server: poller #27 [got 0 values in 0.000010 sec, idle 1 sec]
├─96178 /usr/local/sbin/zabbix_server: poller #28 [got 375 values in 3.153348 sec, getting values]
├─96179 /usr/local/sbin/zabbix_server: poller #29 [got 68 values in 0.064337 sec, getting values]
├─96180 /usr/local/sbin/zabbix_server: poller #30 [got 862 values in 3.930530 sec, idle 1 sec]
├─96181 /usr/local/sbin/zabbix_server: poller #31 [got 758 values in 3.146025 sec, getting values]
├─96183 /usr/local/sbin/zabbix_server: poller #32 [got 235 values in 1.014932 sec, getting values]
├─96185 /usr/local/sbin/zabbix_server: unreachable poller #1 [got 0 values in 0.000022 sec, getting values]
├─96187 /usr/local/sbin/zabbix_server: unreachable poller #2 [got 1 values in 8.014657 sec, getting values]
├─96189 /usr/local/sbin/zabbix_server: unreachable poller #3 [got 0 values in 0.000012 sec, idle 1 sec]
├─96190 /usr/local/sbin/zabbix_server: unreachable poller #4 [got 1 values in 8.010746 sec, getting values]
├─96191 /usr/local/sbin/zabbix_server: unreachable poller #5 [got 1 values in 8.018211 sec, getting values]
├─96192 /usr/local/sbin/zabbix_server: unreachable poller #6 [got 0 values in 0.000015 sec, idle 1 sec]
├─96193 /usr/local/sbin/zabbix_server: unreachable poller #7 [got 0 values in 0.000013 sec, idle 1 sec]
├─96194 /usr/local/sbin/zabbix_server: unreachable poller #8 [got 0 values in 0.000016 sec, getting values]
├─96195 /usr/local/sbin/zabbix_server: unreachable poller #9 [got 0 values in 0.000015 sec, idle 1 sec]
├─96196 /usr/local/sbin/zabbix_server: unreachable poller #10 [got 0 values in 0.000012 sec, idle 1 sec]
├─96197 /usr/local/sbin/zabbix_server: unreachable poller #11 [got 1 values in 8.013568 sec, getting values]
├─96198 /usr/local/sbin/zabbix_server: unreachable poller #12 [got 0 values in 0.000016 sec, idle 1 sec]
├─96199 /usr/local/sbin/zabbix_server: unreachable poller #13 [got 0 values in 0.000015 sec, idle 1 sec]
├─96200 /usr/local/sbin/zabbix_server: unreachable poller #14 [got 0 values in 0.000017 sec, idle 1 sec]
├─96201 /usr/local/sbin/zabbix_server: unreachable poller #15 [got 0 values in 0.000014 sec, getting values]
├─96202 /usr/local/sbin/zabbix_server: unreachable poller #16 [got 0 values in 0.000015 sec, idle 1 sec]
├─96203 /usr/local/sbin/zabbix_server: unreachable poller #17 [got 1 values in 8.013525 sec, getting values]
├─96205 /usr/local/sbin/zabbix_server: unreachable poller #18 [got 0 values in 0.000126 sec, idle 1 sec]
├─96230 /usr/local/sbin/zabbix_server: unreachable poller #19 [got 1 values in 8.015476 sec, getting values]
├─96232 /usr/local/sbin/zabbix_server: unreachable poller #20 [got 0 values in 0.000018 sec, idle 1 sec]
├─96233 /usr/local/sbin/zabbix_server: unreachable poller #21 [got 1 values in 8.012902 sec, getting values]
├─96234 /usr/local/sbin/zabbix_server: unreachable poller #22 [got 0 values in 0.000018 sec, idle 1 sec]
├─96235 /usr/local/sbin/zabbix_server: unreachable poller #23 [got 1 values in 8.009906 sec, getting values]
├─96236 /usr/local/sbin/zabbix_server: unreachable poller #24 [got 0 values in 0.000103 sec, idle 1 sec]
├─96237 /usr/local/sbin/zabbix_server: unreachable poller #25 [got 0 values in 0.000018 sec, idle 1 sec]
├─96238 /usr/local/sbin/zabbix_server: unreachable poller #26 [got 1 values in 8.013481 sec, getting values]
├─96239 /usr/local/sbin/zabbix_server: unreachable poller #27 [got 2 values in 12.020117 sec, getting values]
├─96240 /usr/local/sbin/zabbix_server: unreachable poller #28 [got 0 values in 0.000010 sec, idle 1 sec]
├─96241 /usr/local/sbin/zabbix_server: unreachable poller #29 [got 0 values in 0.000016 sec, idle 1 sec]
├─96242 /usr/local/sbin/zabbix_server: unreachable poller #30 [got 1 values in 8.013187 sec, getting values]
├─96243 /usr/local/sbin/zabbix_server: unreachable poller #31 [got 0 values in 0.000030 sec, idle 1 sec]
├─96244 /usr/local/sbin/zabbix_server: unreachable poller #32 [got 0 values in 0.000064 sec, getting values]
├─96245 /usr/local/sbin/zabbix_server: trapper #1 [processed data in 0.010996 sec, waiting for connection]
├─96246 /usr/local/sbin/zabbix_server: trapper #2 [processed data in 0.007760 sec, waiting for connection]
├─96248 /usr/local/sbin/zabbix_server: trapper #3 [processed data in 0.009104 sec, waiting for connection]
├─96250 /usr/local/sbin/zabbix_server: trapper #4 [processed data in 0.008050 sec, waiting for connection]
├─96252 /usr/local/sbin/zabbix_server: trapper #5 [processed data in 0.007994 sec, waiting for connection]
├─96255 /usr/local/sbin/zabbix_server: icmp pinger #1 [got 0 values in 0.000013 sec, idle 5 sec]
├─96257 /usr/local/sbin/zabbix_server: icmp pinger #2 [got 0 values in 0.000015 sec, idle 5 sec]
├─96258 /usr/local/sbin/zabbix_server: icmp pinger #3 [got 0 values in 0.000015 sec, idle 5 sec]
├─96259 /usr/local/sbin/zabbix_server: icmp pinger #4 [got 0 values in 0.000017 sec, idle 5 sec]
├─96260 /usr/local/sbin/zabbix_server: icmp pinger #5 [got 0 values in 0.000017 sec, idle 5 sec]
├─96261 /usr/local/sbin/zabbix_server: icmp pinger #6 [got 0 values in 0.000019 sec, idle 5 sec]
├─96262 /usr/local/sbin/zabbix_server: icmp pinger #7 [got 0 values in 0.000015 sec, idle 5 sec]
├─96263 /usr/local/sbin/zabbix_server: icmp pinger #8 [got 3 values in 2.202748 sec, idle 5 sec]
├─96264 /usr/local/sbin/zabbix_server: alert manager #1 [sent 0, failed 0 alerts, idle 5.026748 sec during 5.026853 sec]
├─96265 /usr/local/sbin/zabbix_server: alerter #1 started
├─96266 /usr/local/sbin/zabbix_server: alerter #2 started
├─96267 /usr/local/sbin/zabbix_server: alerter #3 started
├─96268 /usr/local/sbin/zabbix_server: alerter #4 started
├─96269 /usr/local/sbin/zabbix_server: alerter #5 started
├─96270 /usr/local/sbin/zabbix_server: alerter #6 started
├─96271 /usr/local/sbin/zabbix_server: alerter #7 started
├─96273 /usr/local/sbin/zabbix_server: alerter #8 started
├─96275 /usr/local/sbin/zabbix_server: preprocessing manager #1 [queued 1, processed 18240 values, idle 4.863318 sec during 5.074969 sec]
├─96277 /usr/local/sbin/zabbix_server: preprocessing worker #1 started
├─96280 /usr/local/sbin/zabbix_server: preprocessing worker #2 started
├─96283 /usr/local/sbin/zabbix_server: preprocessing worker #3 started
├─96285 /usr/local/sbin/zabbix_server: preprocessing worker #4 started
├─96287 /usr/local/sbin/zabbix_server: preprocessing worker #5 started
├─96288 /usr/local/sbin/zabbix_server: preprocessing worker #6 started
├─96289 /usr/local/sbin/zabbix_server: preprocessing worker #7 started
├─96290 /usr/local/sbin/zabbix_server: preprocessing worker #8 started
├─96291 /usr/local/sbin/zabbix_server: lld manager #1 [processed 3 LLD rules during 5.825878 sec]
├─96292 /usr/local/sbin/zabbix_server: lld worker #1 [processed 3 LLD rules, idle 9.160037 sec during 9.324003 sec]
├─96293 /usr/local/sbin/zabbix_server: lld worker #2 [processed 3 LLD rules, idle 8.127109 sec during 8.511826 sec]
└─96294 /usr/local/sbin/zabbix_server: alert syncer [queuing alerts]

[valentins.grins]

Hello,

I see you are using cluster and i assume it is somehow related.
Check the status for your web server(nginx or apache).
Where is the database located? Locally on the same server? If yes then how do you handle database switch with the cluster?
Maybe web server can listen on a certain IP that does not correspond to all nodes?

[walter]

Hi,

DB is a PG cluster on the other side, Zabbix connects the DB with a VIP. web service is worked well.
I have shut down the Zabbix cluster, so in fact, the Zabbix server is a single node.

I'm confused about why once shut down the server, the web page recovered immediately, and the history data still there.
I guess some block happened somewhere, but I don't know how to find it..

[walter]

I found when my DB total connections above some value, the problem comes again(zabbix can't use web page, but the server is still accessed, when shutdown the server, the web can available again)
I have set the max_connection to 200(before is 128), but it can't help.

Any ideas?