Description
Looking at this AWS EC2 Doc It should be possible to add exec > >(tee /var/log/user-data.log|logger -t user-data -s 2>/dev/console) 2>&1 to a user-data script that is run on EC2 initialization.
When running aws ec2 --region eu-west-1 get-console-output --instance-id i-<id> | grep "user-data" (or searching for other patterns that should be present) none are found after the ec2 initialization.
Goal
To read the results and debug information from this initialization script without needing to SSH into the ec2 instance and poll the logs for the shutdown statement. Using the Instance shutdown as the "finished" state has a significant simplification on the deployment process for this repository.
Question
What about this particular setup is not correct such that we are not getting logs out of the aws ec2 get-console-output command.
Alternative answer: What's a better method of retrieving the logs from an EC2 instance.
User-Data Script
#!/bin/bash -xe
# redirect output to log file and console
exec > >(tee /var/log/user-data.log|logger -t user-data -s 2>/dev/console) 2>&1
if [ -n "postgresql,jq" ]
then
yum -y -q update
echo "complete: yum update"
IFS=', ' read -r -a REQS <<< "postgresql,jq"
for REQ in "${REQS[#]}"
do
yum -y -q install $REQ
echo "complete: yum install $REQ"
done
fi
echo "EC2P: ENTERING BOOTSTRAP SCRIPT....."
export PGPASSWORD=$( aws secretsmanager get-secret-value --secret-id <secret_arn> --query SecretString --region eu-west-1 | jq -r . | jq -r .password)
aws s3 cp s3://<query_object> /tmp/postgres-query.sql
echo "EC2P: Starting PSQL Execution"
psql -h <host> \
-p 5432 \
-U <user> \
-o /tmp/postgres-query-result.txt \
<db_name>_db \
< /tmp/postgres-query.sql \
> /tmp/postgres-query-output.txt 2>&1
echo "psql exit code is $?"
echo "EC2P: PSQL Execution Complete"
# since instance_initiated_shutdown_behavior = "terminate"
echo "shutdown"
shutdown
Terraform Declaration Of EC2 Instance
resource "aws_instance" "ec2_provisioner" {
count = var.enabled ? 1 : 0
ami = data.aws_ami.ec2_provisioner.id
iam_instance_profile = var.iam_instance_profile
instance_initiated_shutdown_behavior = "terminate"
instance_type = var.instance_type
root_block_device {
volume_type = "gp2"
volume_size = "16"
delete_on_termination = "true"
}
subnet_id = var.subnet_id
tags = merge(
{
"es:global:component-name" = "${var.component_name}-ec2-provisioner",
"Name" = var.name
},
jsondecode(var.additional_tags)
)
user_data = templatefile(
"${path.module}/user_data.tpl",
{
BASH_SCRIPT = var.bash_script,
PACKAGES = join(",", var.packages)
}
)
volume_tags = {
"Name" = var.name
}
vpc_security_group_ids = [var.security_group_id]
}
The core issue here is that our initialization of the instance is producing too much console output
74295 # > 64 KBs
Which is hitting a size limit built into the get-console-output command
By default, the console output returns buffered information that was posted shortly after an instance transition state (start, stop, reboot, or terminate). This information is available for at least one hour after the most recent post. Only the most recent 64 KB of console output is available
The solution we're going with to fix this issue to to enable SSM and to log into parse the log output.
Wrote a script to add instances to the AWS target group
#!/bin/bash
export AWS_PROFILE=***
export AWS_DEFAULT_REGION=eu-central-1
for INST_NAME in $(aws ec2 describe-instances --query 'Reservations[].Instances[].Tags[?Key==`Name`].Value' --output text | sort); do
echo "check ${INST_NAME} in Target Group"
TARGET_GROUP=$(aws elbv2 describe-target-groups|jq -r '.[]|.[].TargetGroupArn'| grep ${INST_NAME})
RUNNING_INSTANCES=$(aws ec2 describe-instances| jq '.Reservations[].Instances[] | select(.Tags[].Value=="${INST_NAME}")'| jq -r .InstanceId| sort | uniq | wc -l)
COUNT=$(aws elbv2 describe-target-health --target-group-arn ${TARGET_GROUP}|jq -r '.TargetHealthDescriptions[].Target.Id'| wc -l)
if [[ ${RUNNING_INSTANCES} = ${COUNT} ]]; then
echo "VSE OK"
else
echo "dobavit ${RUNNING_INSTANCES} v ${TARGET_GROUP}"
for INSTANCE_ID in $(aws ec2 describe-instances --filter Name=tag-key,Values=Name --query "Reservations[*].Instances[*].{Instance:InstanceId,Name:Tags[?Key=='Name']|[0].Value}"|jq ".[][]|select(.Name==\"${TAGS}\")"|jq -r .Instance); do
ASG=$(aws autoscaling describe-auto-scaling-instances|jq '.AutoScalingInstances'|jq ".[]|select(.InstanceId==\"${INSTANCE_ID}\")"|jq -r .InstanceId)
echo "Updating ${TARGET_GROUP} to add instances from ${ASG}"
aws elbv2 register-targets --target-group-arn ${TARGET_GROUP} --targets "Id="${ASG}
done
fi
done
but he doesn't add. Need select all instances by tag and compare with the number in the target group, if the number is different, then add all instances with the tag to the target group
Update, it's working
for INSTANCE_NAME in $(aws ec2 describe-instances --query 'Reservations[].Instances[].Tags[?Key==`Name`].Value' --output text | sort | uniq ); do
echo "check ${INSTANCE_NAME} in Target Group"
TARGET_GROUP=$(aws elbv2 describe-target-groups|jq -r '.[]|.[].TargetGroupArn'| grep ${INSTANCE_NAME})
if ! [ -z "${TARGET_GROUP}" ]; then
for i in $(echo ${TARGET_GROUP}); do
RUNNING_INSTANCES=$(aws ec2 describe-instances| jq ".Reservations[].Instances[] | select(.Tags[].Value==\"${INSTANCE_NAME}\")"| jq -r .InstanceId| sort | uniq | wc -l)
COUNT=$(aws elbv2 describe-target-health --target-group-arn ${i}|jq -r '.TargetHealthDescriptions[].Target.Id'| wc -l)
if ! [[ ${RUNNING_INSTANCES} = ${COUNT} ]]; then
for INSTANCE_ID in $(aws ec2 describe-instances --filter Name=tag-key,Values=Name --query "Reservations[*].Instances[*].{Instance:InstanceId,Name:Tags[?Key=='Name']|[0].Value}"|jq ".[][]|select(.Name==\"${INSTANCE_NAME}\")"|jq -r .Instance); do
ASG=$(aws autoscaling describe-auto-scaling-instances|jq '.AutoScalingInstances'|jq ".[]|select(.InstanceId==\"${INSTANCE_ID}\")"|jq -r .InstanceId)
aws elbv2 register-targets --target-group-arn ${i} --targets "Id="${ASG}
echo "Updating ${TARGET_GROUP} to add instances from ${ASG}"
done
fi
done
fi
done
I have multiple aws accounts and i don't remember in which aws account this EC2 instance was created, is there any optimal way to figure out in very less time?
Note: i need to know account DNS name or Alias name.(Not account number)
If you have access to the instance you could use Instance metadata API:
[ec2-user ~]$ curl http://169.254.169.254/latest/dynamic/instance-identity/document
It returns json with accountId field.
If you configure AWS CLI for all account, then you can get the Account ID, ARN and user ID.
The script does the following.
Get the list of AWS configuration profile
Loop over all profile
Get a list of All Ec2 public IP address
print account info if IP matched and exit
RUN
./script.sh 52.x.x.x
script.sh
#!/bin/bash
INSTANCE_IP="${1}"
if [ -z "${INSTANCE_IP}" ]; then
echo "pls provide instance IP"
echo "./scipt.sh 54.x.x.x"
exit 1
fi
PROFILE_LIST=$(grep -o "\\[[^]]*]" < ~/.aws/credentials | tr -d "[]")
for PROFILE in $PROFILE_LIST; do
ALL_IPS=$(aws ec2 describe-instances --profile "${PROFILE}" --query "Reservations[].Instances[][PublicIpAddress]" --output text | tr '\r\n' ' ')
echo "looking against profile ${PROFILE}"
for IP in $ALL_IPS; do
if [ "${INSTANCE_IP}" == "${IP}" ]; then
echo "Instance IP matched in below account"
aws sts get-caller-identity
exit 0
fi
done
done
echo "seems like instance not belong to these profile"
echo "${PROFILE_LIST}"
exit 1
loop over accounts
loop over regions
also be aware of lightsail!
I came up with the following and helped me. I didn't exclude the regions that did not have lightsail
for region in `aws ec2 describe-regions --output text --query 'Regions[*].[RegionName]' --region eu-west-1` ; do \
echo $region; \
aws ec2 describe-network-interfaces --output text --filters Name=addresses.private-ip-address,Values="IPv4 address" --region $region ; \
aws lightsail get-instances --region eu-west-1 --output text --query 'instances[*].[name,publicIpAddress]' --region $region; \
done
Amazon recently added the wonderful feature of tagging EC2 instances with key-value pairs to make management of large numbers of VMs a bit easier.
Is there some way to query these tags in the same way as some of the other user-set data? For example:
$ curl http://169.254.169.254/latest/meta-data/placement/availability-zone
us-east-1d
Is there some similar way to query the tags?
The following bash script returns the Name of your current ec2 instance (the value of the "Name" tag). Modify TAG_NAME to your specific case.
TAG_NAME="Name"
INSTANCE_ID="`wget -qO- http://instance-data/latest/meta-data/instance-id`"
REGION="`wget -qO- http://instance-data/latest/meta-data/placement/availability-zone | sed -e 's:\([0-9][0-9]*\)[a-z]*\$:\\1:'`"
TAG_VALUE="`aws ec2 describe-tags --filters "Name=resource-id,Values=$INSTANCE_ID" "Name=key,Values=$TAG_NAME" --region $REGION --output=text | cut -f5`"
To install the aws cli
sudo apt-get install python-pip -y
sudo pip install awscli
In case you use IAM instead of explicit credentials, use these IAM permissions:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [ "ec2:DescribeTags"],
"Resource": ["*"]
}
]
}
Once you've got ec2-metadata and ec2-describe-tags installed (as mentioned in Ranieri's answer above), here's an example shell command to get the "name" of the current instance, assuming you have a "Name=Foo" tag on it.
Assumes EC2_PRIVATE_KEY and EC2_CERT environment variables are set.
ec2-describe-tags \
--filter "resource-type=instance" \
--filter "resource-id=$(ec2-metadata -i | cut -d ' ' -f2)" \
--filter "key=Name" | cut -f5
This returns Foo.
You can use a combination of the AWS metadata tool (to retrieve your instance ID) and the new Tag API to retrieve the tags for the current instance.
You can add this script to your cloud-init user data to download EC2 tags to a local file:
#!/bin/sh
INSTANCE_ID=`wget -qO- http://instance-data/latest/meta-data/instance-id`
REGION=`wget -qO- http://instance-data/latest/meta-data/placement/availability-zone | sed 's/.$//'`
aws ec2 describe-tags --region $REGION --filter "Name=resource-id,Values=$INSTANCE_ID" --output=text | sed -r 's/TAGS\t(.*)\t.*\t.*\t(.*)/\1="\2"/' > /etc/ec2-tags
You need the AWS CLI tools installed on your system: you can either install them with a packages section in a cloud-config file before the script, use an AMI that already includes them, or add an apt or yum command at the beginning of the script.
In order to access EC2 tags you need a policy like this one in your instance's IAM role:
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "Stmt1409309287000",
"Effect": "Allow",
"Action": [
"ec2:DescribeTags"
],
"Resource": [
"*"
]
}
]
}
The instance's EC2 tags will available in /etc/ec2-tags in this format:
FOO="Bar"
Name="EC2 tags with cloud-init"
You can include the file as-is in a shell script using . /etc/ec2-tags, for example:
#!/bin/sh
. /etc/ec2-tags
echo $Name
The tags are downloaded during instance initialization, so they will not reflect subsequent changes.
The script and IAM policy are based on itaifrenkel's answer.
If you are not in the default availability zone the results from overthink would return empty.
ec2-describe-tags \
--region \
$(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e "s/.$//") \
--filter \
resource-id=$(curl --silent http://169.254.169.254/latest/meta-data/instance-id)
If you want to add a filter to get a specific tag (elasticbeanstalk:environment-name in my case) then you can do this.
ec2-describe-tags \
--region \
$(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e "s/.$//") \
--filter \
resource-id=$(curl --silent http://169.254.169.254/latest/meta-data/instance-id) \
--filter \
key=elasticbeanstalk:environment-name | cut -f5
And to get only the value for the tag that I filtered on, we pipe to cut and get the fifth field.
ec2-describe-tags \
--region \
$(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e "s/.$//") \
--filter \
resource-id=$(curl --silent http://169.254.169.254/latest/meta-data/instance-id) \
--filter \
key=elasticbeanstalk:environment-name | cut -f5
You can alternatively use the describe-instances cli call rather than describe-tags:
This example shows how to get the value of tag 'my-tag-name' for the instance:
aws ec2 describe-instances \
--instance-id $(curl -s http://169.254.169.254/latest/meta-data/instance-id) \
--query "Reservations[*].Instances[*].Tags[?Key=='my-tag-name'].Value" \
--region ap-southeast-2 --output text
Change the region to suit your local circumstances. This may be useful where your instance has the describe-instances privilege but not describe-tags in the instance profile policy
I have pieced together the following that is hopefully simpler and cleaner than some of the existing answers and uses only the AWS CLI and no additional tools.
This code example shows how to get the value of tag 'myTag' for the current EC2 instance:
Using describe-tags:
export AWS_DEFAULT_REGION=us-east-1
instance_id=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
aws ec2 describe-tags \
--filters "Name=resource-id,Values=$instance_id" 'Name=key,Values=myTag' \
--query 'Tags[].Value' --output text
Or, alternatively, using describe-instances:
aws ec2 describe-instances --instance-id $instance_id \
--query 'Reservations[].Instances[].Tags[?Key==`myTag`].Value' --output text
For Python:
from boto import utils, ec2
from os import environ
# import keys from os.env or use default (not secure)
aws_access_key_id = environ.get('AWS_ACCESS_KEY_ID', failobj='XXXXXXXXXXX')
aws_secret_access_key = environ.get('AWS_SECRET_ACCESS_KEY', failobj='XXXXXXXXXXXXXXXXXXXXX')
#load metadata , if = {} we are on localhost
# http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AESDG-chapter-instancedata.html
instance_metadata = utils.get_instance_metadata(timeout=0.5, num_retries=1)
region = instance_metadata['placement']['availability-zone'][:-1]
instance_id = instance_metadata['instance-id']
conn = ec2.connect_to_region(region, aws_access_key_id=aws_access_key_id, aws_secret_access_key=aws_secret_access_key)
# get tag status for our instance_id using filters
# http://docs.aws.amazon.com/AWSEC2/latest/CommandLineReference/ApiReference-cmd-DescribeTags.html
tags = conn.get_all_tags(filters={'resource-id': instance_id, 'key': 'status'})
if tags:
instance_status = tags[0].value
else:
instance_status = None
logging.error('no status tag for '+region+' '+instance_id)
A variation on some of the answers above but this is how I got the value of a specific tag from the user-data script on an instance
REGION=$(curl http://instance-data/latest/meta-data/placement/availability-zone | sed 's/.$//')
INSTANCE_ID=$(curl -s http://instance-data/latest/meta-data/instance-id)
TAG_VALUE=$(aws ec2 describe-tags --region $REGION --filters "Name=resource-id,Values=$INSTANCE_ID" "Name=key,Values='<TAG_NAME_HERE>'" | jq -r '.Tags[].Value')
Starting January 2022, this should be also available directly via ec2 metadata api (if enabled).
curl http://169.254.169.254/latest/meta-data/tags/instance
https://aws.amazon.com/about-aws/whats-new/2022/01/instance-tags-amazon-ec2-instance-metadata-service/
Using the AWS 'user data' and 'meta data' APIs its possible to write a script which wraps puppet to start a puppet run with a custom cert name.
First start an aws instance with custom user data: 'role:webserver'
#!/bin/bash
# Find the name from the user data passed in on instance creation
USER=$(curl -s "http://169.254.169.254/latest/user-data")
IFS=':' read -ra UDATA <<< "$USER"
# Find the instance ID from the meta data api
ID=$(curl -s "http://169.254.169.254/latest/meta-data/instance-id")
CERTNAME=${UDATA[1]}.$ID.aws
echo "Running Puppet for certname: " $CERTNAME
puppet agent -t --certname=$CERTNAME
This calls puppet with a certname like 'webserver.i-hfg453.aws' you can then create a node manifest called 'webserver' and puppets 'fuzzy node matching' will mean it is used to provision all webservers.
This example assumes you build on a base image with puppet installed etc.
Benefits:
1) You don't have to pass round your credentials
2) You can be as granular as you like with the role configs.
Jq + ec2metadata makes it a little nicer. I'm using cf and have access to the region. Otherwise you can grab it in bash.
aws ec2 describe-tags --region $REGION \
--filters "Name=resource-id,Values=`ec2metadata --instance-id`" | jq --raw-output \
'.Tags[] | select(.Key=="TAG_NAME") | .Value'
No jq.
aws ec2 describe-tags --region us-west-2 \
--filters "Name=resource-id,Values=`ec2-metadata --instance-id | cut -d " " -f 2`" \
--query 'Tags[?Key==`Name`].Value' \
--output text
Download and run a standalone executable to do that.
Sometimes one cannot install awscli that depends on python. docker might be out of the picture too.
Here is my implementation in golang:
https://github.com/hmalphettes/go-ec2-describe-tags
The Metadata tool seems to no longer be available, but that was an unnecessary dependency anyway.
Follow the AWS documentation to have the instance's profile grant it the "ec2:DescribeTags" action in a policy, restricting the target resources as much as you wish. (If you need a profile for another reason then you'll need to merge policies into a new profile-linked role).
Then:
aws --region $(curl -s http://169.254.169.254/latest/meta-data/placement/availability-zone | sed -e 's/.$//') ec2 describe-tags --filters Name=resource-type,Values=instance Name=resource-id,Values=$(curl http://169.254.169.254/latest/meta-data/instance-id) Name=key,Values=Name |
perl -nwe 'print "$1\n" if /"Value": "([^"]+)/;'
Well there are lots of good answers here but none quite worked for me exactly out of the box, I think the CLI has been updated since some of them and I do like using the CLI. The following single command works out of the box for me in 2021 (as long as the instance's IAM role is allowed to describe-tags).
aws ec2 describe-tags \
--region "$(ec2-metadata -z | cut -d' ' -f2 | sed 's/.$//')" \
--filters "Name=resource-id,Values=$(ec2-metadata --instance-id | cut -d " " -f 2)" \
--query 'Tags[?Key==`Name`].Value' \
--output text
AWS has recently announced support for instance tags in Instance Metadata Service: https://aws.amazon.com/about-aws/whats-new/2022/01/instance-tags-amazon-ec2-instance-metadata-service/
If you have have the tag metadata option enabled for an instance, you can simply do
$ TOKEN=`curl -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 900"`
$ curl -H "X-aws-ec2-metadata-token: $TOKEN" -v http://169.254.169.254/latest/meta-data/tags/instance
It is possible to get Instance tags from within the instance via metadata.
First, allow access to tags in instance metadata as explained here
Then, run this command for IMDSv1, Refer
curl http://169.254.169.254/latest/meta-data/tags/instance/Name
or this command for IMDSv2
TOKEN=`curl -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600"` \
&& curl -H "X-aws-ec2-metadata-token: $TOKEN" -v http://169.254.169.254/latest/meta-data/tags/instance
Install AWS CLI:
curl "https://s3.amazonaws.com/aws-cli/awscli-bundle.zip" -o "awscli-bundle.zip"
sudo apt-get install unzip
unzip awscli-bundle.zip
sudo ./awscli-bundle/install -i /usr/local/aws -b /usr/local/bin/aws
Get the tags for the current instance:
aws ec2 describe-tags --filters "Name=resource-id,Values=`ec2metadata --instance-id`"
Outputs:
{
"Tags": [
{
"ResourceType": "instance",
"ResourceId": "i-6a7e559d",
"Value": "Webserver",
"Key": "Name"
}
]
}
Use a bit of perl to extract the tags:
aws ec2 describe-tags --filters \
"Name=resource-id,Values=`ec2metadata --instance-id`" | \
perl -ne 'print "$1\n" if /\"Value\": \"(.*?)\"/'
Returns:
Webserver
For those crazy enough to use Fish shell on EC2, here's a handy snippet for your /home/ec2-user/.config/fish/config.fish. The hostdata command now will list all your tags as well as the public IP and hostname.
set -x INSTANCE_ID (wget -qO- http://instance-data/latest/meta-data/instance-id)
set -x REGION (wget -qO- http://instance-data/latest/meta-data/placement/availability-zone | sed 's/.$//')
function hostdata
aws ec2 describe-tags --region $REGION --filter "Name=resource-id,Values=$INSTANCE_ID" --output=text | sed -r 's/TAGS\t(.*)\t.*\t.*\t(.*)/\1="\2"/'
ec2-metadata | grep public-hostname
ec2-metadata | grep public-ipv4
end