Opensearch didn't print any log on RHEL

OpenSearch
1

so i’m using the current latest version 3.3.2

previously I had installed on rocky linux 9 using tar installation and it’s running well

but when I installed it on RHEL 8, it won’t print any log. the service was active but no log was printed. i suspect the problem is with systemd, and I already tried many different systemd configurations on RHEL 8 but got nothing

this is systemd config that works on rocky linux 9

[Unit]
Description=OpenSearch
Documentation=https://opensearch.org/
Wants=network-online.target
After=network-online.target

[Service]
Type=simple
User=elkadmin
Group=elkadmin

# Change this to your actual extraction directory
Environment=OPENSEARCH_HOME=/opensearch/opensearch-3.3.2
Environment=OPENSEARCH_PATH_CONF=/opensearch/opensearch-3.3.2/config

# If you want logs under /var/log/opensearch:
# Environment=OPENSEARCH_LOG_DIR=/var/log/opensearch

ExecStart=/opensearch/opensearch-3.3.2/bin/opensearch
ExecStop=/opensearch/opensearch-3.3.2/bin/opensearch -p ${OPENSEARCH_HOME}/pid --stop

# Java opts already included in jvm.options
# You MUST use JDK21 since tarball bundles it

LimitNOFILE=65536
LimitNPROC=4096
LimitMEMLOCK=infinity
TimeoutStopSec=180

# Needed to allow mlockall
CapabilityBoundingSet=CAP_IPC_LOCK
AmbientCapabilities=CAP_IPC_LOCK
NoNewPrivileges=true

[Install]
WantedBy=multi-user.target

in rocky, I can see there is a log named my-application.log

[root@training opensearch-3.3.2]# ll logs/
total 2780
-rw-r--r--. 1 elkadmin elkadmin   59869 Dec  2 21:10 gc.log
-rw-r--r--. 1 elkadmin elkadmin    2868 Dec  2 10:02 gc.log.00
-rw-r--r--. 1 elkadmin elkadmin   13256 Dec  2 10:02 gc.log.01
-rw-r--r--. 1 elkadmin elkadmin    2867 Dec  2 10:12 gc.log.02
-rw-r--r--. 1 elkadmin elkadmin   22724 Dec  2 10:13 gc.log.03
-rw-r--r--. 1 elkadmin elkadmin    2869 Dec  2 10:15 gc.log.04
-rw-r--r--. 1 elkadmin elkadmin   58438 Dec  2 10:18 gc.log.05
-rw-r--r--. 1 elkadmin elkadmin    4739 Dec  2 10:18 gc.log.06
-rw-r--r--. 1 elkadmin elkadmin    4861 Dec  2 10:18 gc.log.07
-rw-r--r--. 1 elkadmin elkadmin    4741 Dec  2 10:18 gc.log.08
-rw-r--r--. 1 elkadmin elkadmin  545758 Dec  2 21:01 gc.log.09
-rw-r--r--. 1 root     root        4733 Dec  2 19:31 gc.log.10
-rw-r--r--. 1 root     root        4859 Dec  2 19:31 gc.log.11
-rw-r--r--. 1 elkadmin elkadmin    4733 Dec  2 21:01 gc.log.12
-rw-r--r--. 1 elkadmin elkadmin    4856 Dec  2 21:01 gc.log.13
-rw-r--r--. 1 elkadmin elkadmin    4732 Dec  2 21:01 gc.log.14
-rw-r-----. 1 elkadmin elkadmin  849634 Dec  2 21:07 my-application.log
-rw-r-----. 1 elkadmin elkadmin    9164 Dec  2 21:02 my-application_deprecation.json
-rw-r-----. 1 elkadmin elkadmin    3570 Dec  2 21:02 my-application_deprecation.log
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_index_indexing_slowlog.json
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_index_indexing_slowlog.log
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_index_search_slowlog.json
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_index_search_slowlog.log
-rw-r-----. 1 elkadmin elkadmin 1171944 Dec  2 21:07 my-application_server.json
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_task_detailslog.json
-rw-r-----. 1 elkadmin elkadmin       0 Dec  2 10:13 my-application_task_detailslog.log
[root@training opensearch-3.3.2]#

but all I see on RHEL is just gc.log. i used exactly the same configuration for OpenSearch as on rocky as well as the systemd (at first)

on rhel 8, opensearch service is active(running) but the port doesn’t listen at all and no log in the desire location

Can anyone help me with this?

thanks

2

the selinux on both systems were set to permissive

3

@darkCruel The issue is in the system entropy. RHEL 8 has low entropy, and the OpenSearch 3.x service won’t start.

You can try the following as a workaround

yum install rng-tools
service rngd start