Dealing with Database Instance connectivity issues

Public accessLink to this anchor

ProblemLink to this anchor

I cannot connect to my Database Instance through the public network.

Possible causesLink to this anchor

• The Database Instance TLS certificate is outdated
• Your allowed IPs are not properly configured
• You have reached the maximum number of connections
• The Database Instance is experiencing instabilities due to a high load

SolutionLink to this anchor

You can check the following points to identify and act on what might be causing the issue:

1. If TLS is enabled on the Database Instance, make sure the certificate is up to date, and that your client application is properly configured.

2. Make sure your ACLs are properly configured.

3. Make sure your Database Instance has not reached the maximum number of connections stipulated in the advanced settings of the Database Instance. You can monitor the number of connections on Cockpit. You can also adjust the advanced settings to accept a higher number of connections.

4. Monitor other usage metrics on Cockpit to:

   • Check if the memory usage is nominal. High memory usage could trigger OOM Kills and cause disconnection
   • Check Database Instance logs and look for anything else that could explain the issue

Private accessLink to this anchor

ProblemLink to this anchor

I cannot connect to my Database Instance through a Private Network.

Possible causesLink to this anchor

• The Database Instance TLS certificate is outdated
• Client network issue
• You have reached the maximum number of connections
• The Database Instance is experiencing instabilities due to a high load

SolutionLink to this anchor

You can carry out the following actions:

1. Try to connect to the Database Instance from the public endpoint, if one is available, to identify the possible origin (network or instance). This information can help you or the support team to identify the issue.

2. Use Cockpit to check database logs and look for any activity or behavior that could explain the issue.

3. Create a support ticket if the first two steps do not help troubleshoot the issue. In the body of the ticket, make sure you provide:

   • The resource ID of resource from which the connection was attempted
   • The output of the rdb_troubleshoot.sh script, indicated below. Make sure you execute the script on the machine from which the connection was attempted.

Database Instance connectivity check script

rdb_troubleshoot.sh:

#!/bin/bash
set -o nounset
if [ -z "$INSTANCE_IP" ]; then
    echo "INSTANCE_IP is a mandatory environment variable."
    echo "e.g. export INSTANCE_IP=<xxx.xxx.xxx.xxx>"
    exit 1
fi
if [ -z "$INSTANCE_PORT" ]; then
    echo "INSTANCE_PORT is a mandatory environment variable."
    echo "e.g. export INSTANCE_PORT=<xxxxx>"
    exit 1
fi
function header() {
    echo -e "\n # ${1}"
    echo -e "---------------------------------\n"
}
echo -e "\nRDB troubleshooting script\nThis script will run for several minutes to get enough information."
header "Host information"
if ! [ -x "$(command -v uname)" ]; then
  echo 'Skipped: uname command is not availabe.'
else
  uname -a
fi
header "Host connectivity check"
if ! [ -x "$(command -v ping)" ]; then
  echo 'Skipped: ping command is not availabe.'
else
  ping -c 5 ${INSTANCE_IP}
fi
header "Database connectivity check"
if ! [ -x "$(command -v telnet)" ]; then
  # try to fallback on curl telnet
  if ! [ -x "$(command -v curl)" ]; then
    echo "Skipped: neither telnet nor curl command are availabe."
  else
    echo "(using curl)"
    timeout 2 curl -v telnet://$INSTANCE_IP:$INSTANCE_PORT
  fi
else
  echo "(using telnet)"
  echo -n | telnet ${INSTANCE_IP} ${INSTANCE_PORT}
fi
header "Ip configuration check"
if ! [ -x "$(command -v ip)" ]; then
  echo 'Skipped: ip command is not availabe.'
else
  echo -e "Interfaces:\n- \n"
  ip a
  echo -e "\nNeighbour:\n- \n"
  TEST_ITERATION=30
  TEST_INTERVAL=10 # seconds
  # Iterate a few times to try to catch relevant info
  for ((i=1;i<=$TEST_ITERATION;i++)); do
    echo -e "\nIteration $i:\n"
    ip neighbour show
    echo -e "\nWaiting ${TEST_INTERVAL}s...\n"
    sleep $TEST_INTERVAL
  done
  echo -e "\nRoute:\n-\n"
  ip route
fi

Run the script in a terminal:

export INSTANCE_IP=<xxx.xxx.xxx.xxx>
export INSTANCE_PORT=<xxxxx>
./troubleshoot.sh