Explanation/Reference:
Explanation:
A: You will see two files starting with id_rsa. id_rsa is the private key and id_rsa.pub is public key.
E: The .ssh/known_hosts file
In order to use public-key secure connection with other hosts (ssh, scp, sftp) there is a special directory, ~/
.ssh/, where passphrases and public keys are stored. Normally you wouldn't need to know the gory details, but from time to time a host will change its public key and then you have difficulty using ssh or scp with that host, and have to edit a file named known_hosts.
If you try to ssh to another computer, but get an error message that warns about a changed or incorrect public key, then it is probably just a case of that host changing its public key. (It is possible, though usually not the case, that malicious hacking is involved.) Unless you actually suspect hacker involvement, you can edit the file ~/.ssh/known_hosts using your usual text editor (vi, emacs, nedit, or pico) and delete any line with the name of that host.
Then when you try to ssh that host again, it will be like the first time ever; ssh will ask you if you want to accept a new public key, you type the whole word yes, and everything will proceed normally from there.
Here is what a typical ~/.ssh/known_hosts file might contain. Note that newton is represented on two different lines:
newton 1024 35
153438062610297067329638677441205712613292203533062535600064224677647442245028855505
387934431717435134842994423656065076260604296084868001730665553662299156116414854701
274715680961503198280525759778667306417179500370189017139564144825610347509023078143
132936185076849630461827976942220442313116255293297021841
ucsub 1024 37
132170811640421742212085598383135714069016332111955003414250071326834884018721183646
445780180633494496866895830879394309011412231102757022090299732775466435482517698989
962531081214859205054227533597152962802400251809883548442498002326460312850336779152
617243800769119880843882425555806081435017335194477605333
simpson 1024 41
840896920592494584403453622735282634536002054701576247765078766974814128393752943151
071629834843909016027026612791643752972116459602750267266908365259665072736159491719
667576217171370458928680504368847255632477925660234893185547218857655484574619075125
36847079297627580626353420887972219277539015703446529603
newton, 128.138.249.8 ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAIEA0d7Aoure0toNJ
+YMYi61QP2ka8m5x5ZQlT7obP8CK3eropfqsMPPY6uiyIh9vpiFX2r1LHcbx139+vG6HOtVvuS8
+IfMDtawm3WQvRuOopz3vVy5GtMwtaOgehsXoT930Ryev1bH5myPtWKlipITsOd2sX9k3tvjrmme4KCGG ss