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Re:Bastions on demand in an AWS VPC by debaserab2 on Tuesday June 23, 2020 @10:26PM (#23623267)
Alternately you can inventory your instances in AWS Systems Manager and start an SSH session directly from the AWS CLI itself [1] -- no Bastion servers or SSH key management necessary, pure IAM access only.

[1] https://docs.aws.amazon.com/systems-manager/latest/userguide...

Re:Bastions on demand in an AWS VPC by m1keil on Wednesday June 24, 2020 @04:44AM (#23625665)
Also worth mentioning you can also tunnel with SSM, so it's possible to use plain SSH or do anything that you usually used to accomplish with bastion.

https://github.com/elpy1/ssh-over-ssm

Re:Bastions on demand in an AWS VPC by vladvasiliu on Wednesday June 24, 2020 @08:10AM (#23626942)
While it's possible to do port forwarding with SSM [0] I would encourage people to test it well.

I've tried using it for development, and it was a terrible experience. The connections would hang all the time for no reason. I ended up starting an SSH session (via SSM) and done the port forwarding via that...

[0] https://docs.aws.amazon.com/systems-manager/latest/userguide...

Re:Bastions on demand in an AWS VPC by voganmother42 on Wednesday June 24, 2020 @12:14AM (#23624026)
Or you can run ssm agent on a fargate task for double the fun (just need to register as hybrid and remember to clean up (scheduled lambda works a treat for this)
Re:Bastions on demand in an AWS VPC by 616c on Wednesday June 24, 2020 @12:53AM (#23624250)
This is a neat concept and made reading the article and thread worth it. Thanks.
Re:Bastions on demand in an AWS VPC by WaxProlix on Tuesday June 23, 2020 @11:37PM (#23623765)
Always glad to see one of our products mentioned :)

Huge shameless plug for the coolness that is Session Manager, I can only think of a few scenarios where you wouldn't just prefer it over the alternatives. If you haven't played with it (or other SSM stuff), you totally should! It's cool and useful and easy and more or less free.

Re:Bastions on demand in an AWS VPC by debaserab2 on Wednesday June 24, 2020 @12:34AM (#23624133)
It was a total no-brainer once we discovered it. Really nice work.

If you're interested in more feedback, I'd be happy to share. As with many things AWS, there were some undocumented rougher edges that took some trial and error to figure. Although the end result was well worth it. Totally understand if you're not on HN to do that sort of thing, though.

Re:Bastions on demand in an AWS VPC by WaxProlix on Wednesday June 24, 2020 @12:59AM (#23624277)
Hey, I'm all ears. Just an engineer, but customer feedback is taken super seriously (albeit with a tragically long turnaround time - it's a surprisingly large organization with a lot of irons on a lot of fires). I'll totally pass on anything you have to say though.

e: or put an email in your profile and I'll even reach out!

Re:Bastions on demand in an AWS VPC by debaserab2 on Wednesday June 24, 2020 @02:29AM (#23624750)
I don't keep an email in my profile but you can find me here: [email protected]
Re:Bastions on demand in an AWS VPC by zozos on Wednesday June 24, 2020 @07:48AM (#23626782)
Is there a way to use SSM without using the access keys? I feel using access keys is incredibly not secure because rotating keys is a hassle and people might not do them all the time.

Also can u restrict access to ssh through ssm to certain ips?

Maybe I might have missed these, so any help would be appreciated.

Re:Bastions on demand in an AWS VPC by vladvasiliu on Wednesday June 24, 2020 @08:04AM (#23626903)
> Is there a way to use SSM without using the access keys? I feel using access keys is incredibly not secure because rotating keys is a hassle and people might not do them all the time.

Technically there is, you can use federated login. Might not be very convenient, depending on your identity provider.

A solution I use, while not technically "not using access kys" is storing them in the system credential store with aws-vault [0]. Works on Windows, Linux and Mac. And you can combine this with multi factor auth.

> Also can u restrict access to ssh through ssm to certain ips?

Yes, with an IAM policy. The policy below requires connecting with an MFA and from a specific IP range. It only allows connecting to a specific instance.

  {
    "Version": "2012-10-17",
    "Statement": [
      {
        "Sid": "VisualEditor0",
        "Effect": "Allow",
        "Action": "ssm:StartSession",
        "Resource": [
          "arn:aws:ec2:eu-west-3:123123123123:instance/i-123123123123",
          "arn:aws:ssm:eu-west-3::document/AWS-StartPortForwardingSession",
          "arn:aws:ssm:eu-west-3::document/AWS-StartSSHSession"
        ],
        "Condition": {
          "IpAddress": {
            "aws:SourceIp": "1.2.3.4/32"
          },
          "BoolIfExists": {
            "aws:MultiFactorAuthPresent": "true"
          }
        }
      }
    ]
  }
[0] AWS Vault: https://github.com/99designs/aws-vault/
Re:Bastions on demand in an AWS VPC by a012 on Tuesday June 23, 2020 @11:57PM (#23623923)
I'd love to use SSM with other OSes (i.e. FreeBSD) than just Amazon Linux & Ubuntu which are supported.
Re:Bastions on demand in an AWS VPC by WaxProlix on Wednesday June 24, 2020 @12:21AM (#23624059)
You can! The agent can be installed on almost any linux flavor, and is open source on GitHub, so it can be compiled and installed on any EC2 machines (or on-prem machines) you want. (This might not be easy, I haven't done it myself)

If you can make a good case for it, open a ticket or make a stink on the forums and there's a chance an engineer can be tasked to add it to their list of Officially Supported Platforms. This is how eg raspbian got added, though I don't know if the program is still running for adding platforms as it's been a few years.

Re:Bastions on demand in an AWS VPC by kevinkeller on Wednesday June 24, 2020 @12:24AM (#23624078)
Does this still work if folks are authenticated via federation/SAML instead of as IAM users?
Re:Bastions on demand in an AWS VPC by ciceryadam on Wednesday June 24, 2020 @12:52AM (#23624238)
Yep.
Re:Bastions on demand in an AWS VPC by oneplane on Tuesday June 23, 2020 @10:52PM (#23623471)
Downside is that it doubles access options when you have a mixed environment, i.e. multiple clouds and/or non-cloud servers. Other than that it's a great solution if IAM is your default user source.