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mwagz
01-23-2007, 03:01 PM
Up until yesterday, i could ssh to a remote system in my network.But now......

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
26:cd:d9:4d:f8:7e:14:27:a5:8b:0a:48:09:0e:a5:d2.
Please contact your system administrator.
Add correct host key in /root/.ssh/known_hosts to get rid of this message.
Offending key in /root/.ssh/known_hosts:2
RSA host key for ppgp1 has changed and you have requested strict checking.
Host key verification failed.



Host and remote OS : knoppix linux. How can I resolve this?

turbine
01-23-2007, 03:12 PM
Delete the entry in /root/.ssh/known_hosts. Then rerun ssh.

mwagz
01-23-2007, 03:35 PM
the file known_hosts:





|1|M+cvGv+SeYGSYVOb4v4lp6Z4+W4=|l8aAQJc9eBpm2D7N1B HOnTWj7O0= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAzWUC1SrB0jFuU3xgtSBosK Uyv+1CO8QDDNyXxjaXhl7t+G2I5oIDO84gn xQ0wi4DcK3kjA3LvF8HAaBTgAlsg6XwLrHaPr4ycBBxinER3FR nfEbsnAPX99610ztI3VaF+IpfRC4GshQm2GrpFxAGFzUAboRhF XxQmSCjL91b7tg72OHveXezgZYtl94qz5ITTSnznNQ7je3dWVE xSHd jMOw1oIKd0lfcqMkxJEyfWpksm1qKhSi9pXgUrRfDftsSjXO8+ tfYHcPKI0FaJW4ahndwMuhSdjHALN1T1OwgCJDHQRC0O5vumHP ZAqUoLwnTVvOSvReqzYWi6rxoaQVCVw==
2 |1|hDWQnSY1XTXHLFrqZxTuPstyWCE=|wZcOa1MR3YKoY58zl4 mnMSYFbf4= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAzWUC1SrB0jFuU3xgtSBosK Uyv+1CO8QDDNyXxjaXhl7t+G2I5oIDO84gn xQ0wi4DcK3kjA3LvF8HAaBTgAlsg6XwLrHaPr4ycBBxinER3FR nfEbsnAPX99610ztI3VaF+IpfRC4GshQm2GrpFxAGFzUAboRhF XxQmSCjL91b7tg72OHveXezgZYtl94qz5ITTSnznNQ7je3dWVE xSHd jMOw1oIKd0lfcqMkxJEyfWpksm1qKhSi9pXgUrRfDftsSjXO8+ tfYHcPKI0FaJW4ahndwMuhSdjHALN1T1OwgCJDHQRC0O5vumHP ZAqUoLwnTVvOSvReqzYWi6rxoaQVCVw==
3 |1|S/M8oi1teW4zZ57VTm+A+2wTVmQ=|tVsatPZDOESbvS2DpHuaO7i sMSM= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA5qHr8lFmegMewySeOC9Wyi jSY7MirGbiUKHw6Vkfl9sOG+18xiVyUUL63 bScJox5MxjzJgqT+0Q01sB2eesAR3kjV/NBsKO8grd0Cy5s35PQrZZ98eunHCUiMh7xxCvojlp+pD5K6qTn D1R3g5zM8uyAgeFoEZupDSeUjMDCWZBOa0NP+uSB2leq7YBVpy BLIdUey9+M+vow5njZoaZ dWFHFbsZ9KpLjoOvGSPfen3rbk4JFlM/WYLMFlprdUXynWQ6VLEn4o+OPMY1Jq1L/H6cju4d5g/0YVjw6HHnJq3n6hROAfoDrJ682V50nf4Z8rWK40W6me2aKXCvB XH1URw==
4 |1|yI4+cuZsGb5aE0oKUgDrFrU9jx8=|W/AiZL8cASN8OnchpwMRnOFiqs0= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA5qHr8lFmegMewySeOC9Wyi jSY7MirGbiUKHw6Vkfl9sOG+18xiVyUUL63 bScJox5MxjzJgqT+0Q01sB2eesAR3kjV/NBsKO8grd0Cy5s35PQrZZ98eunHCUiMh7xxCvojlp+pD5K6qTn D1R3g5zM8uyAgeFoEZupDSeUjMDCWZBOa0NP+uSB2leq7YBVpy BLIdUey9+M+vow5njZoaZ dWFHFbsZ9KpLjoOvGSPfen3rbk4JFlM/WYLMFlprdUXynWQ6VLEn4o+OPMY1Jq1L/H6cju4d5g/0YVjw6HHnJq3n6hROAfoDrJ682V50nf4Z8rWK40W6me2aKXCvB XH1URw==
5 |1|N9hBtYaUbieggT8JUt3FsrXfYsA=|vZWoWkcWMAJ5xfLFjl P2eOLBGkg= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEArmHD5zr9IoFS/OcWa02r1Ug0ESYcSa0WsGMeYTFHWsteljkDXARrffg/A 185dBQ8swUHq90wo+A17L7ZpluEIBPBSLv35XkmxqeRRtlUvE/VZV2/WqZdWZuhWTKs2KmkhZI+OMJi/atSCXgy6zxsm0jaUgM3+ke7p4KExW7+d9t6ObZWNlC1PjzrwR4 8vkvKAYHau3iDqoYHLDHDIRB qfGMrp/hdSkQucPo4ZI/s4eeYMjZOGgzSkYhvjfbo7H1R46/7+aIts4WduVVA1Btjfp2TDfpnabeBWGGMDpWtjpkn6ARxZMLg/QwKnn4YhDaXlJyScLqtsbyEAz/CZc05rQ==
6 |1|WKVSlPrQSiy2eCyyp6hGfv7fm+k=|6kh4wC/leuhbVKJyNj441QogIVc= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA5Xr3h/U5k8lqi8I6y+grBA4Lsce1Jixp/acqAele339nbuXgixePhJ+3M TFfhydG7xKCU3H1GPUEqBpumwAfNLwHyDVuaBZ5Il64EHPgBUI hY3Z24v9/+QD0eqSWhE77SvTSvb1VzY7lvTXlWUIZ/JRl46dFuYlD+0uu61l0gW+spBMTI3RtBip7RICojNuzqgEDT50 iehcnok0K+0W YexEdrcslwW4cMty/5bA+GD/NMciKCdNeBJK2xsKwA30Q/ouvMSBrr62EQX9xCeavwyvY3Sic1cn7K5JkGRwhKU5SF3+f1a5 kONB9TQJEn8RgQPliOZVXx5bM/EsttFJ6Rw==
7 |1|yFe3DdwsH+C8D/2BwKz+8uy9bis=|K8zn+TxpW++mvnQ+wwpOC02pSqc= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA5Xr3h/U5k8lqi8I6y+grBA4Lsce1Jixp/acqAele339nbuXgixePhJ+3M TFfhydG7xKCU3H1GPUEqBpumwAfNLwHyDVuaBZ5Il64EHPgBUI hY3Z24v9/+QD0eqSWhE77SvTSvb1VzY7lvTXlWUIZ/JRl46dFuYlD+0uu61l0gW+spBMTI3RtBip7RICojNuzqgEDT50 iehcnok0K+0W YexEdrcslwW4cMty/5bA+GD/NMciKCdNeBJK2xsKwA30Q/ouvMSBrr62EQX9xCeavwyvY3Sic1cn7K5JkGRwhKU5SF3+f1a5 kONB9TQJEn8RgQPliOZVXx5bM/EsttFJ6Rw==
8 |1|IU2Tj3Gs+oScD0ZhrfZSfdwBDtU=|jRyPOL3KFlDwpPaGj/sYvsU73Vs= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA9j5ksltVZJ7E9P3ydQ9HKJ 2NoNeNHAb8i+Q/EmoBHSKFIXiriSM03v2jO SQrhe5vRpVMIsgV8CHDAwM0TCmiIKbz7LG0ZUGlDUfOnvMg9XO e3FhF2wAT85ZTgQgCaOYU9eehH3A2ak2OqknOw2z9KgUmfNPDm cSI/86aNYCnROXzVxHP4n3JLdEPOtArLq7RleXnJHSVP9LD2ttKW0d JYN3N7BSKFPstTEGhZkh/CltAGN+RVApUHlYLEvlPUuJ3LZmRJqadw9RfNc4nil0ZK2EBAN QNs53qF8ilMLq010aeEGHAgaj0jcObhwaXVGTL6cc6kzRk879E 9vDMXs+5UQ==
9 |1|1lnHAmcF/Bx43eJ1glSbC9fVga4=|PEY8gndHmm6DMaBIZTJf5HGvsP0= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA9j5ksltVZJ7E9P3ydQ9HKJ 2NoNeNHAb8i+Q/EmoBHSKFIXiriSM03v2jO SQrhe5vRpVMIsgV8CHDAwM0TCmiIKbz7LG0ZUGlDUfOnvMg9XO e3FhF2wAT85ZTgQgCaOYU9eehH3A2ak2OqknOw2z9KgUmfNPDm cSI/86aNYCnROXzVxHP4n3JLdEPOtArLq7RleXnJHSVP9LD2ttKW0d JYN3N7BSKFPstTEGhZkh/CltAGN+RVApUHlYLEvlPUuJ3LZmRJqadw9RfNc4nil0ZK2EBAN QNs53qF8ilMLq010aeEGHAgaj0jcObhwaXVGTL6cc6kzRk879E 9vDMXs+5UQ==

turbine
01-23-2007, 03:46 PM
I'd delete the whole file and start ssh again as if it was the first time
that you ran it. I don't have a remote_hosts file but I can run
ssh 192.168.0.3 to connect to one of the computers on my lan and ssh
will create the file for me.

mwagz
01-24-2007, 08:22 AM
Deleting the contents did work...I can npw ssh to the remote host.....thx alot....but
what actually happened? and what happened after the deletion?

angor
01-24-2007, 09:30 AM
When you first contact an sshd on a machine, this will leave a "fingerprint"
of that machine in your .ssh/known_hosts. At any later connection to that machine
your ssh will consult that fingerprint and warn you if it doesn't match with
what the remote site offers. Probably the sshd was a new installation - at that
time a new fingerprint would have been generated, causing the mismatch.
Simply deleting line 2 in your known_hosts would have sufficed to remove the
out-of-date entry.

However: Try to make *really sure* that the other side is really what it's supposed
to be! It could be a hijacked IP address...

turbine
01-24-2007, 01:12 PM
What happens to me is this. When I shut down my entire system, including my dsl modem, and then come back up, some or all of my ip addresses change. I'm using dynamic ip's and my dsl modem makes the assignments. I still get the same range of ip's but they're distributed differently over the various machines. This causes the mismatches in my known_hosts file. I usually just delete the file.