You can bind multiple SSH key pairs to a Linux instance to allow access to the instance by using the key pairs. You can also replace existing key pairs.

Prerequisites

The public key information of new key pairs is obtained. For more information, see View public key information.

Background information

After an SSH key pair is bound to a Linux instance, the public key of the key pair is stored in the ~/.ssh/authorized_keys file. You can modify this file to add multiple key pairs or replace existing key pairs.
Note When you bind SSH key pairs to instances in the ECS console, you can bind only one key pair to each instance. If you only need one key pair, we recommend that you bind the key pair in the ECS console. For more information, see Bind an SSH key pair to an instance.

Procedure

  1. Use an existing key pair to log on to the ECS instance.
  2. Run the vim .ssh/authorized_keys command to open the ~/.ssh/authorized_keys file.
  3. Add or replace public key information.
    • Add public key information: You can add and save new public key information under the existing public key information. 
      ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCys3aOkFm1Xh8iN0lijeQF5mz9Iw/FV/bUUduZjauiJa1KQJSF4+czKtqMAv38QEspiWStkSfpTn1g9qeUhfxxxxxxxxxx+XjPsf22fRem+v7MHMa7KnZWiHJxO62D4Ihvv2hKfskz8K44xxxxxxxxxx+u17IaL2l2ri8q9YdvVHt0Mw5TpCkERWGoBPE1Y8vxFb97TaE5+zc+2+eff6xxxxxxxxxx/feMeCxpx6Lhc2NEpHIPxMpjOv1IytKiDfWcezA2xxxxxxxxxx/YudCmJ8HTCnLId5LpirbNE4X08Bk7tXZAxxxxxxxxxx/FKB1Cxw1TbGMTfWxxxxxxxxxx imported-openssh-key
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDdlrdZwV3+GF9q7rhc6vYrExwT4WU4fsaRcVXGV2Mg9RHex21hl1au77GkmnIgukBZjywlQOT4GDdsJy2nBOdJPrCEBIPxxxxxxxxxxx/fctNuKjcmMMOA8YUT+sJKn3l7rCLkesE+S5880yNdRjBiiUy40kyr7Y+fqGVdSOHGMXZQPpkBtojcxxxxxxxxxx/htEqGa/Jq4fH7bR6CYQ2XgH/hCap29Mdi/G5Tx1nbUKuIHdMWOPvjxxxxxxxxxx+lHtTGiAIRG1riyNRVC47ZEVCg9iTWWGrWFvxxxxxxxxxx/9H9mPCO1Xt2fxxxxxxxxBtmR imported-openssh-key
      Note If the ~/.ssh/authorized_keys file contains the information of multiple public keys, you can log on to the instance by using any of the corresponding private keys.
    • Replace public key information: You can delete existing public key information to add and save new public key information. 
      ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDdlrdZwV3+GF9q7rhc6vYrExwT4WU4fsaRcVXGV2Mg9RHex21hl1au77GkmnIgukBZjywlQOT4GDdsJy2nBOdJPrCEBIP6t0Mk5aPkK/fctNuKjcmMMOA8YUT+sJKn3l7rCLkesE+S5880yNdRjBiiUy40kyr7Y+fqGVdSOHGMXZQPpkBtojcV14uAy0yV6/htEqGa/Jq4fH7bR6CYQ2XgH/hCap29Mdi/G5Tx1nbUKuIHdMWOPvjGACGcXclex+lHtTGiAIRG1riyNRVC47ZEVCg9iTWWGrWFvVlnI0E3Deb/9H9mPCO1Xt2fxxxxxxxxBtmR imported-openssh-key

    If you can log on to the instance by using new private keys, the key pairs are added or replaced.