Linux Services Management

This section covers managing the EPMware Agent on Linux servers, including systemd services, background processes, and Linux-specific considerations.

Linux Management Options

The EPMware Agent can run on Linux as:

• systemd Service
  Modern Linux distributions (recommended)

• Background Process
  Traditional approach using nohup

• Start/Stop Scripts
  Manual control procedures

Management Overview

systemd Service (Recommended)

For modern Linux distributions: - Automatic startup on boot - Process supervision - Dependency management - Integrated logging

Background Process

Traditional Unix approach: - Simple to implement - Works on all systems - Manual management - Less robust

Init.d Scripts

For older systems: - SysV init compatibility - Legacy system support - Manual dependency handling

Quick Management Commands

Check Agent Status

# systemd status
systemctl status epmware-agent

# Process check
ps aux | grep epmware-agent

# Recent logs
tail -n 20 /home/epmadmin/logs/agent.log

Start Agent

# Via systemd
sudo systemctl start epmware-agent

# Via background process
cd /home/epmadmin
nohup ./ew_target_service.sh > agent.out 2>&1 &

Stop Agent

# Via systemd
sudo systemctl stop epmware-agent

# Via process kill
pkill -f epmware-agent

systemd Service Configuration

Creating Service File

Create /etc/systemd/system/epmware-agent.service:

[Unit]
Description=EPMware Agent Service
After=network.target
Wants=network-online.target

[Service]
Type=simple
User=epmadmin
Group=epmadmin
WorkingDirectory=/home/epmadmin
ExecStart=/usr/bin/java -jar /home/epmadmin/epmware-agent.jar --spring.config.name=agent
ExecStop=/bin/kill -TERM $MAINPID
Restart=always
RestartSec=30
StandardOutput=journal
StandardError=journal
SyslogIdentifier=epmware-agent

# Environment variables
Environment="JAVA_HOME=/usr/java/latest"
Environment="PATH=/usr/java/latest/bin:/usr/local/bin:/usr/bin:/bin"

# Resource limits
LimitNOFILE=65536
LimitNPROC=32768

# Memory limits
MemoryLimit=2G

[Install]
WantedBy=multi-user.target

Enabling Service

# Reload systemd configuration
sudo systemctl daemon-reload

# Enable service for auto-start
sudo systemctl enable epmware-agent

# Start the service
sudo systemctl start epmware-agent

# Check status
systemctl status epmware-agent

Process Management

Process Monitoring

Monitor agent process:

#!/bin/bash
# monitor_agent.sh

# Check if running
if pgrep -f "epmware-agent" > /dev/null; then
    echo "Agent is running"

    # Get process details
    ps aux | grep epmware-agent | grep -v grep

    # Check resource usage
    pid=$(pgrep -f "epmware-agent")
    echo "Memory usage:"
    ps -o pid,vsz,rss,comm -p $pid

    echo "CPU usage:"
    top -b -n 1 -p $pid | tail -1
else
    echo "Agent is NOT running"
    exit 1
fi

Process Limits

Configure resource limits:

# /etc/security/limits.d/epmware.conf
epmadmin soft nofile 65536
epmadmin hard nofile 65536
epmadmin soft nproc 32768
epmadmin hard nproc 32768
epmadmin soft memlock unlimited
epmadmin hard memlock unlimited

Log Management

systemd Journal

View logs with journalctl:

# View all agent logs
journalctl -u epmware-agent

# Follow logs in real-time
journalctl -u epmware-agent -f

# View logs since boot
journalctl -u epmware-agent -b

# View last 100 lines
journalctl -u epmware-agent -n 100

# Export logs
journalctl -u epmware-agent > agent-systemd.log

rsyslog Integration

Configure rsyslog for agent:

# /etc/rsyslog.d/epmware-agent.conf
if $programname == 'epmware-agent' then /var/log/epmware/agent.log
& stop

logrotate Configuration

Manage log rotation:

# /etc/logrotate.d/epmware-agent
/home/epmadmin/logs/*.log {
    daily
    rotate 30
    compress
    delaycompress
    missingok
    notifempty
    create 644 epmadmin epmadmin
    sharedscripts
    postrotate
        systemctl reload epmware-agent
    endscript
}

Init.d Script (Legacy Systems)

For older Linux distributions:

#!/bin/bash
# /etc/init.d/epmware-agent
### BEGIN INIT INFO
# Provides:          epmware-agent
# Required-Start:    $network $syslog
# Required-Stop:     $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: EPMware Agent
# Description:       EPMware metadata deployment agent
### END INIT INFO

AGENT_USER=epmadmin
AGENT_HOME=/home/$AGENT_USER
AGENT_SCRIPT=$AGENT_HOME/ew_target_service.sh
PID_FILE=/var/run/epmware-agent.pid

case "$1" in
    start)
        echo "Starting EPMware Agent..."
        su - $AGENT_USER -c "cd $AGENT_HOME && nohup $AGENT_SCRIPT > /dev/null 2>&1 &"
        echo $! > $PID_FILE
        echo "Agent started."
        ;;
    stop)
        echo "Stopping EPMware Agent..."
        if [ -f $PID_FILE ]; then
            kill $(cat $PID_FILE)
            rm $PID_FILE
        fi
        echo "Agent stopped."
        ;;
    restart)
        $0 stop
        sleep 2
        $0 start
        ;;
    status)
        if [ -f $PID_FILE ] && ps -p $(cat $PID_FILE) > /dev/null; then
            echo "Agent is running (PID: $(cat $PID_FILE))"
        else
            echo "Agent is not running"
        fi
        ;;
    *)
        echo "Usage: $0 {start|stop|restart|status}"
        exit 1
        ;;
esac
exit 0

Monitoring and Alerting

Health Check Script

Automated health monitoring:

#!/bin/bash
# health_check.sh

# Configuration
AGENT_USER="epmadmin"
AGENT_HOME="/home/$AGENT_USER"
ALERT_EMAIL="admin@company.com"
MAX_MEMORY=2048  # MB
MAX_CPU=80       # Percent

# Check process
if ! pgrep -f "epmware-agent" > /dev/null; then
    echo "CRITICAL: Agent not running" | mail -s "EPMware Agent Down" $ALERT_EMAIL
    exit 2
fi

# Check memory usage
PID=$(pgrep -f "epmware-agent")
MEMORY=$(ps -o rss= -p $PID | awk '{print int($1/1024)}')
if [ $MEMORY -gt $MAX_MEMORY ]; then
    echo "WARNING: High memory usage: ${MEMORY}MB" | mail -s "EPMware Agent Memory Alert" $ALERT_EMAIL
fi

# Check CPU usage
CPU=$(top -b -n 1 -p $PID | tail -1 | awk '{print int($9)}')
if [ $CPU -gt $MAX_CPU ]; then
    echo "WARNING: High CPU usage: ${CPU}%" | mail -s "EPMware Agent CPU Alert" $ALERT_EMAIL
fi

# Check last poll time
LAST_POLL=$(tail -1 $AGENT_HOME/logs/agent-poll.log | awk '{print $1" "$2}')
LAST_EPOCH=$(date -d "$LAST_POLL" +%s)
NOW_EPOCH=$(date +%s)
DIFF=$((NOW_EPOCH - LAST_EPOCH))

if [ $DIFF -gt 300 ]; then  # More than 5 minutes
    echo "WARNING: No polling for $DIFF seconds" | mail -s "EPMware Agent Polling Alert" $ALERT_EMAIL
fi

echo "Agent health check completed"

Integration with Monitoring Systems

Nagios/Icinga

#!/bin/bash
# check_epmware_agent.sh - Nagios plugin

STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3

# Check if process is running
if pgrep -f "epmware-agent" > /dev/null; then
    # Check last poll time
    LAST_POLL=$(stat -c %Y /home/epmadmin/logs/agent-poll.log)
    NOW=$(date +%s)
    DIFF=$((NOW - LAST_POLL))

    if [ $DIFF -lt 60 ]; then
        echo "OK - Agent running and polling"
        exit $STATE_OK
    elif [ $DIFF -lt 300 ]; then
        echo "WARNING - Agent running but slow polling ($DIFF seconds)"
        exit $STATE_WARNING
    else
        echo "CRITICAL - Agent running but not polling ($DIFF seconds)"
        exit $STATE_CRITICAL
    fi
else
    echo "CRITICAL - Agent not running"
    exit $STATE_CRITICAL
fi

Zabbix

{
    "zabbix_export": {
        "version": "5.0",
        "templates": [{
            "template": "EPMware Agent",
            "name": "EPMware Agent Monitoring",
            "items": [{
                "name": "Agent process running",
                "key": "proc.num[java,epmadmin,,epmware-agent]",
                "value_type": "UNSIGNED",
                "triggers": [{
                    "expression": "{last()}=0",
                    "name": "EPMware Agent is down",
                    "priority": "HIGH"
                }]
            }]
        }]
    }
}

Performance Tuning

JVM Options

Optimize Java settings:

# In ew_target_service.sh or systemd service
JAVA_OPTS="-server"
JAVA_OPTS="$JAVA_OPTS -Xms1024m -Xmx2048m"
JAVA_OPTS="$JAVA_OPTS -XX:+UseG1GC"
JAVA_OPTS="$JAVA_OPTS -XX:MaxGCPauseMillis=200"
JAVA_OPTS="$JAVA_OPTS -XX:+HeapDumpOnOutOfMemoryError"
JAVA_OPTS="$JAVA_OPTS -XX:HeapDumpPath=/var/log/epmware"

java $JAVA_OPTS -jar epmware-agent.jar --spring.config.name=agent

System Tuning

Kernel parameters for performance:

# /etc/sysctl.d/epmware.conf
# Network tuning
net.core.rmem_max = 134217728
net.core.wmem_max = 134217728
net.ipv4.tcp_rmem = 4096 87380 134217728
net.ipv4.tcp_wmem = 4096 65536 134217728

# File handles
fs.file-max = 2097152

# Process limits
kernel.pid_max = 4194304

# Apply settings
sudo sysctl -p /etc/sysctl.d/epmware.conf

Troubleshooting

Common Linux Issues

Issue	Diagnosis	Solution
Service won't start	Check systemctl status	Review journal logs
Permission denied	ls -la file permissions	Fix ownership/permissions
Cannot find Java	which java	Update PATH or JAVA_HOME
Out of memory	dmesg | grep -i memory	Increase heap size or system RAM

Debug Mode

Enable detailed debugging:

# Add to systemd service or script
export LOGGING_LEVEL_ROOT=DEBUG
export LOGGING_LEVEL_COM_EPMWARE=TRACE

# Or in service file
Environment="LOGGING_LEVEL_ROOT=DEBUG"
Environment="LOGGING_LEVEL_COM_EPMWARE=TRACE"

Security Hardening

SELinux Configuration

For Red Hat/CentOS with SELinux:

# Create custom policy
cat > epmware_agent.te << EOF
module epmware_agent 1.0;

require {
    type java_exec_t;
    type user_home_t;
    class file { read write execute };
    class process { transition };
}

allow java_exec_t user_home_t:file { read write execute };
EOF

# Compile and install policy
checkmodule -M -m -o epmware_agent.mod epmware_agent.te
semodule_package -o epmware_agent.pp -m epmware_agent.mod
semodule -i epmware_agent.pp

AppArmor Profile

For Ubuntu/Debian with AppArmor:

# /etc/apparmor.d/epmware-agent
#include <tunables/global>

/home/epmadmin/epmware-agent.jar {
  #include <abstractions/base>
  #include <abstractions/java>

  /home/epmadmin/ r,
  /home/epmadmin/** rw,
  /var/log/epmware/** rw,

  network inet stream,
  network inet6 stream,
}

Best Practices

Linux-Specific Recommendations

1. Use systemd - For modern distributions
2. Monitor with journalctl - Centralized logging
3. Configure limits - Set appropriate resource limits
4. Regular updates - Keep system packages updated
5. Security hardening - Implement SELinux/AppArmor

Maintenance Guidelines

1. Log rotation - Configure logrotate
2. Resource monitoring - Track memory and CPU
3. Backup configurations - Regular config backups
4. Update documentation - Keep runbooks current
5. Test recovery - Verify restart procedures

Next Steps

• Background Process Setup - Traditional process management
• Start and Stop Procedures - Operation procedures
• Agent Logs - Log management
• Monitoring - Monitoring setup