Fix Server Hangs/Freezes

Access During a Hang

If SSH is unresponsive:

• Use Hostxpeed VNC/Console from control panel
• Use "Force Reboot" option
• Check resource graphs in control panel

Diagnose the Hang

uptime
top -b -n 1 | head -10

free -h

df -h
iostat -x 1 3

ps aux | awk '$8=="D" {print}'

Common Freeze Causes

1. Fork Bomb (Too Many Processes)

ps aux | wc -l
sysctl kernel.pid_max

2. Filesystem Hang

mount | grep nfs
cat /proc/mounts
ps aux | awk '$8=="D"'

3. Swap Thrashing

vmstat 1
sudo swapoff -a

4. Full Disk

df -h
df -i

5. Firewall Lockout

sudo iptables -L -n
sudo ufw status

Emergency Recovery

echo 1 > /proc/sys/kernel/sysrq
echo s > /proc/sysrq-trigger
echo u > /proc/sysrq-trigger
echo b > /proc/sysrq-trigger

Post-Reboot Investigation

sudo journalctl -b -1 -n 200 --no-pager | grep -i "error|fail|panic"
sudo dmesg | grep -i "hung|blocked"
sudo egrep -i "killed process|oom" /var/log/kern.log