Centos SSH keys

Shockey

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hello, I trying to setup a hadoop cluster here. I hit a bump in the road of trying to set it up it seems. when i try and copy the id_rsa.pub to authorized_keys says it doesn't exit. I go to the folder (.ssh) and it also doesn't show it.

i ran first.
Code:
ssh-keygen -t rsa

then

Code:
[hadoop@master .ssh]$ cat id_rsa.pub /home/hadoop/.ssh/authorized_keys
(key removed.)
cat: /home/hadoop/.ssh/authorized_keys: No such file or directory

Anyone shed some light on this and how to get this to work correctly.


Thanks in advance!
 

keenan

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cat reads all files listed on its command line and dumps them to stdout. Your command is trying to read the authorized_keys file (which doesn't exist yet), not write to it. You probably meant to do:
Code:
cat id_rsa.pub > /home/hadoop/.ssh/authorized_keys

Which takes the stdout from cat and redirects it into the file.
 

Shockey

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Nov 24, 2008
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cat reads all files listed on its command line and dumps them to stdout. Your command is trying to read the authorized_keys file (which doesn't exist yet), not write to it. You probably meant to do:
Code:
cat id_rsa.pub > /home/hadoop/.ssh/authorized_keys

Which takes the stdout from cat and redirects it into the file.

I guess my copy and paste to putty didn't work correctly.

this is the original command from the tutorial

Code:
cat /home/hadoop/.ssh/id_rsa.pub >>  /home/hadoop/.ssh/authorized_keys

My laziness i guess got the better of me. Your code work out for me. Thank you for the quick reply and explaining it!
 

keenan

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For future reference, >> is append, > will overwrite the existing file.
 

Shockey

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For future reference, >> is append, > will overwrite the existing file.

Alright thank you.

Do you happen to know how to find where java is installed on centos system?

it came installed i beleive cause i ran yum update and seen it was being updated.
 

keenan

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Alright thank you.

Do you happen to know how to find where java is installed on centos system?

it came installed i beleive cause i ran yum update and seen it was being updated.

Generally Linux is not like Windows, where programs are installed to a single directory. Java will likely have files all over the filesystem, though RedHat distros sometimes use /opt for things like Java, I'm not sure, I don't use them.

If you just want to know the path to the java binary, you can use 'which java'.
 

Shockey

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Joined
Nov 24, 2008
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Generally Linux is not like Windows, where programs are installed to a single directory. Java will likely have files all over the filesystem, though RedHat distros sometimes use /opt for things like Java, I'm not sure, I don't use them.

If you just want to know the path to the java binary, you can use 'which java'.


which java did the trick. I need it to run hadoop which is written in java. :)

Thanks for the help.
 
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