# Public Key Authentication getting errors **URL:** \ **Category:** Linux on Servers\ **Created:** [December 6, 2021, 7:47pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256 "2021-12-06T19:47:03Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 6, 2021, 7:47pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/1 "2021-12-06T19:47:03Z")
Hi, Everyone. I am trying to learn Linux and watched both Jay and Andrew Mallet tutorial on how to configure Public Authentication but I am hitting a brick wall with 2 problems. ``` 1. Problem is, although I was successfully copied over the Public Key to target server I am still getting prompt for a password instead of passphrase 2. If set the "PasswordAuthentication" to no I get hit in "sshd_config" I get an error of Permission denied (publickey,gssapi-keyex,gssapi-with-mic) ``` Here is the configuration from sshd\_config file: > #Port 22 > #AddressFamily any > #ListenAddress 0.0.0.0 > #ListenAddress :: > > HostKey /etc/ssh/ssh\_host\_rsa\_key > #HostKey /etc/ssh/ssh\_host\_dsa\_key > HostKey /etc/ssh/ssh\_host\_ecdsa\_key > HostKey /etc/ssh/ssh\_host\_ed25519\_key > > #Ciphers and keying > #RekeyLimit default none > > #Logging > #SyslogFacility AUTH > SyslogFacility AUTHPRIV > #LogLevel INFO > > #Authentication: > > #LoginGraceTime 2m > PermitRootLogin no > #StrictModes yes > #MaxAuthTries 6 > #MaxSessions 10 > > PubkeyAuthentication yes > > #The default is to check both .ssh/authorized\_keys and .ssh/authorized\_keys2 > #but this is overridden so installations will only check .ssh/authorized\_keys > AuthorizedKeysFile ~/.ssh/authorized\_keys > > #AuthorizedPrincipalsFile none > > #AuthorizedKeysCommand none > #AuthorizedKeysCommandUser nobody > > #For this to work you will also need host keys in /etc/ssh/ssh\_known\_hosts > #HostbasedAuthentication no > #Change to yes if you don’t trust ~/.ssh/known\_hosts for > #HostbasedAuthentication > #IgnoreUserKnownHosts no > #Don’t read the user’s ~/.rhosts and ~/.shosts files > #IgnoreRhosts yes > > #To disable tunneled clear text passwords, change to no here! > #PasswordAuthentication yes > #PermitEmptyPasswords no > PasswordAuthentication yes > > #Change to no to disable s/key passwords > #ChallengeResponseAuthentication yes > ChallengeResponseAuthentication no > > #Kerberos options > #KerberosAuthentication no > #KerberosOrLocalPasswd yes > #KerberosTicketCleanup yes > #KerberosGetAFSToken no > #KerberosUseKuserok yes > > #GSSAPI options > GSSAPIAuthentication yes > GSSAPICleanupCredentials no > #GSSAPIStrictAcceptorCheck yes > #GSSAPIKeyExchange no > #GSSAPIEnablek5users no > > #Set this to ‘yes’ to enable PAM authentication, account processing, > #and session processing. If this is enabled, PAM authentication will > #be allowed through the ChallengeResponseAuthentication and > #PasswordAuthentication. Depending on your PAM configuration, > #PAM authentication via ChallengeResponseAuthentication may bypass > #the setting of “PermitRootLogin without-password”. > #If you just want the PAM account and session checks to run without > #PAM authentication, then enable this but set PasswordAuthentication > #and ChallengeResponseAuthentication to ‘no’. > #WARNING: ‘UsePAM no’ is not supported in Red Hat Enterprise Linux and may cause several > #problems. > UsePAM yes > > #AllowAgentForwarding yes > #AllowTcpForwarding yes > #GatewayPorts no > X11Forwarding yes > #X11DisplayOffset 10 > #X11UseLocalhost yes > #PermitTTY yes > #PrintMotd yes > #PrintLastLog yes > #TCPKeepAlive yes > #UseLogin no > #UsePrivilegeSeparation sandbox > #PermitUserEnvironment no > #Compression delayed > #ClientAliveInterval 0 > #ClientAliveCountMax 3 > #ShowPatchLevel no > #UseDNS yes > #PidFile /var/run/sshd.pid > #MaxStartups 10:30:100 > #PermitTunnel no > #ChrootDirectory none > #VersionAddendum none > > #no default banner path > #Banner none > > #Accept locale-related environment variables > AcceptEnv LANG LC\_CTYPE LC\_NUMERIC LC\_TIME LC\_COLLATE LC\_MONETARY LC\_MESSAGES > AcceptEnv LC\_PAPER LC\_NAME LC\_ADDRESS LC\_TELEPHONE LC\_MEASUREMENT > AcceptEnv LC\_IDENTIFICATION LC\_ALL LANGUAGE > AcceptEnv XMODIFIERS > > #override default of no subsystems > Subsystem sftp /usr/libexec/openssh/sftp-server > > #Example of overriding settings on a per-user basis > #Match User anoncvs > #X11Forwarding no > #AllowTcpForwarding no > #PermitTTY no > #ForceCommand cvs server Hope you can point out what I have overlooked, if you need more info please let me know and this is a vm for studying so I can provide everything in this VM. ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 6, 2021, 11:16pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/2 "2021-12-06T23:16:52Z")
> [@adelaide-Guy](#): > > AuthorizedKeysFile ~/.ssh/authorized\_keys This is the line that jumps out to me, I’ve only ever seen it expressed ```auto AuthorizedKeysFile .ssh/authorized_keys ``` Also cat the ~/.ssh/authorized\_keys file and ensure that the line for your “from” host matches exactly your id\_rsa.pub that you generated on the “from” machine… ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 7, 2021, 8:24am UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/3 "2021-12-07T08:24:20Z")
Thank you for the response, In regards to “AuthorizedKeysFile ~/.ssh/authorized\_keys” I have only change while troubleshooting my issue. I was guessing maybe it is not seeing the right location of the authorized\_keys Performing cat ~/.ssh/authorized\_keys on my target server and cat ~/.ssh/authorized\_keys are the same > [tux@server1 .ssh]$ cat id\_rsa2.pub > ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCYxjBMogG96DCq3VdR0QvaAfYz4mh4RwdNKaxI24v4r0hBi6Yp+mpdWGkK9kcr968NOtCWQV9/zpZqwvv8SnPy/J9otQjRAeFR3PumAgfSD2VMxIrXDY5dameV1Ez+fhcSvCW4h5K1w1HiEu72zn9TC7Btt3DNAsOdeeVpYsmTBEEDPjmMn8XCUNzBlVj0FALiVCTwaXT06blEeQvKW9k6CULyDCeySW7V62KZW3NrUDOqzXAjzcjOMZd8EOWCb8KAG2cOfYcmnB+NWLwJn7WBGXeCKuRjYjwl25TkiA90T1EtmVFk4EzVfbljprQq1LIelknN439qXusImCbtCeMD tux@server1 > [tux@server2 ~]$ cat ~/.ssh/authorized\_keys > ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCYxjBMogG96DCq3VdR0QvaAfYz4mh4RwdNKaxI24v4r0hBi6Yp+mpdWGkK9kcr968NOtCWQV9/zpZqwvv8SnPy/J9otQjRAeFR3PumAgfSD2VMxIrXDY5dameV1Ez+fhcSvCW4h5K1w1HiEu72zn9TC7Btt3DNAsOdeeVpYsmTBEEDPjmMn8XCUNzBlVj0FALiVCTwaXT06blEeQvKW9k6CULyDCeySW7V62KZW3NrUDOqzXAjzcjOMZd8EOWCb8KAG2cOfYcmnB+NWLwJn7WBGXeCKuRjYjwl25TkiA90T1EtmVFk4EzVfbljprQq1LIelknN439qXusImCbtCeMD tux@server1 ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 7, 2021, 2:37pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/4 "2021-12-07T14:37:51Z")
Ok, I’ve replicated that error message on a couple of my machines, it’s a client-side issue. It happens when the client does not expose the private key properly. In any case, the client need not have an authorized\_keys file, it only needs to have the private key to log into another host (which then must have the public key in its authorized\_keys file). Here’s how my client looks when working properly (‘optional’ means you need not have that file in your client-side .ssh for proper function): ```auto efahl@client$ pwd /home/efahl efahl@client$ ll -d .ssh drwx------ 2 efahl efahl 4096 Dec 2 12:04 .ssh/ efahl@client$ ll .ssh total 32 -rw-rw-r-- 1 efahl efahl 2454 Nov 17 17:39 authorized_keys <-- optional -rw-r--r-- 1 efahl efahl 322 Dec 2 12:04 config <-- optional -rw------- 1 efahl efahl 2610 Nov 13 13:53 id_rsa <-- MANDATORY private key -rw-r--r-- 1 efahl efahl 573 Nov 13 13:53 id_rsa.pub <-- optional ``` It may be permissions? (Wild guess, I only tested by removing the private key.) Check and make sure that your .ssh directory and private key looks like above (‘chmod 700 .ssh’ and ‘chmod 600 .ssh/id\_rsa’), as I recall having client side issues with that before (on Windows maybe???). Also that ‘2’ in your key file name looks weird. Did ssh-keygen do that? I’ve only seen the ‘id\_rsa’ files without the ‘2’… ---
**Author:** ![Buffy](https://community.learnlinux.tv/user_avatar/community.learnlinux.tv/buffy/32/497_2.png) [@Buffy](https://community.learnlinux.tv/u/Buffy)\ **Post date:** [December 7, 2021, 3:34pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/5 "2021-12-07T15:34:25Z")
Yes, your ~/.ssh directory should have group and other permissions removed, as ssh will not work otherwise. This policy is in place because home directories don’t necessarily exclude group and other access. I wouldn’t consider your public key(s) to be “optional” in any way as they are half of your key pair; it(they) really shouldn’t be removed. Parts of ssh, such as ssh-copy-id, won’t work without it being there. ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 7, 2021, 8:02pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/6 "2021-12-07T20:02:41Z")
In regards to “id\_rsa2.pub” this was generated by me. Because when following Andrew Mullet’s tutorial in pluralsight I thought I need to use sudo to generate the keys. Realizing I can use my regular account without using sudo, I regenerated the keys and named it “id\_rsa2.pub” As I check the files and folders, I have the permission already set to 600 for “.ssh/id\_rsa” and 700 for .ssh > [tux@server1 ~]$ ll -d .ssh > drwx------. 2 tux tux 131 Dec 7 05:40 .ssh > [tux@server1 ~]$ ll .ssh > total 28 > -rw-r–r–. 1 tux root 135 Dec 3 08:01 config > -rw-------. 1 tux tux 1766 Dec 3 07:34 id\_rsa > -rw-------. 1 tux tux 1766 Dec 6 05:18 id\_rsa2 > -rw-r–r–. 1 tux tux 393 Dec 6 05:18 id\_rsa2.pub > -rw-r–r–. 1 tux tux 393 Dec 3 07:34 id\_rsa.pub > -rw-r–r–. 1 tux tux 347 Dec 7 05:40 known\_hosts > -rw-r–r–. 1 tux tux 347 Dec 7 05:40 known\_hosts\_backup Also I don’t have “authorized\_keys” on my client computer, because I have not tried connecting back from server2 to server1. Is this the possible cause of issue? In my “config” file here is the content, is this the similar as yours: > [tux@server1 ~]$ cat ~/.ssh/config > Host server1 > Hostname 192.168.10.243 > User tux > Port 22 > > Host server2 > Hostname 192.168.10.242 > User tux > Port 22 Just checking maybe this is the issue. ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 7, 2021, 8:56pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/7 "2021-12-07T20:56:39Z")
Aha, there’s your issue. Server2 is using the contents of ‘id\_rsa2.pub’ via its authorized\_keys contents and server1 is using ‘id\_rsa.pub’ on the client side. On server1, try doing ‘ssh-copy-id server2’ (it should ask password), then after it completes ‘ssh server2’ should log you in without a password prompt. When that works, only then can you change server2’s config to enable ‘PasswordAuthentication yes’, restart the sshd on server2 and you’ve secured it… Since this is just initial config, you probably should just start over: 1. empty server2 authorized\_keys, 2. delete server1 .ssh directory altogether (well, copy your ‘config’ somewhere), 3. on server1 ‘ssh-keygen’ to make a new keypair, then ‘ssh-copy-id server2’ 4. ‘ssh server2’ and see what happens (To be complete, you could use ‘ssh -i ~/.ssh/id\_rsa2 tux@server2’ on the client, but that just complicates things, which is probably inappropriate at this point on the learning curve…) Edit: fix a couple of typos. ---
**Author:** ![hulxmash](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/h/e9c0ed/32.png) [@hulxmash](https://community.learnlinux.tv/u/hulxmash)\ **Post date:** [December 8, 2021, 7:30am UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/8 "2021-12-08T07:30:08Z")
or if you are using both keys, try adding the line IdentityFile ~/.ssh/id\_rsa2 to the server2 block on your config file. It should look like Host server2 Hostname 192.168.10.242 User tux Port 22 IdentityFile ~/.ssh/id\_rsa2 Then your ssh connection will automatically use the proper key file. Nice catch efahl! ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 9, 2021, 8:53pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/9 "2021-12-09T20:53:57Z")
As per advice I have deleted .ssh folder on both server1 and server2. and executed “ssh-keygen -t rsa” on server1 and after generating the public I then created the “config” file and then executed “chown $USER” and “chmod 644” to the “config” file. I copied it to server2 using ssh-copy-id -i id\_rsa.pub server2. After doing this it still uses the password instead of the key. I did the same process in server2 to check if I will have the same problem and it worked perfectly. I have a snapshot of server1 from the beginning (no configuration aside from updates and network settings) I followed the same procedure and it worked perfectly. It must be some setting in either sshd\_config or somewhere that may be causing this on server1. Anyway thank you for for trying to help me. Probably I’ll just redo the image for server1. ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 9, 2021, 9:56pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/10 "2021-12-09T21:56:36Z")
Here are some more things to check: 1. Make sure PubKeyAuthentication is “yes” in your /etc/ssh/sshd\_config file. The default is “yes”, so if it’s commented out, then it’s turned on. 2. Run “ssh -G serverN” and look at the output. Gah! Too much to pick through by hand, so on each machine do “ssh -G serverN \> serverN\_output”, then get the two “\*\_output” files on one machine. Run “diff server1\_output server2\_output” and you’ll see what’s different between them. Hopefully the diff output will point to the problem. In any case, report back, we’re curious about what’s going on here! (It _should_ “just work”, but…) ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 11, 2021, 11:54am UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/11 "2021-12-11T11:54:25Z")
This is what I got after comparing the files generated when connecting to each server > [tux@server1 ~]$ diff server2\_output server1\_output > 2c2 > > > hostname 192.168.10.242 > > * * * > > > hostname 192.168.10.243 ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 11, 2021, 5:34pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/12 "2021-12-11T17:34:29Z")
Well, that didn’t tell us much, did it? If you’re willing to spend more time on it, you can run sshd in “extended test mode” and have it dump its configuration with ‘sudo sshd -T’ (sshd just reads its configs and keys, dumps everything, then quits). If you redirect the output into files and diff them, maybe that will be more informative (although it looks to me like most of what is important is already in the ‘ssh -G’ output). ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 11, 2021, 7:49pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/13 "2021-12-11T19:49:34Z")
Thanks for the help man, I am all good in spending more time on this, that is my purpose I want to learn. Unfortunately running “sudo sshd -T server2 \> server2\_output2” did not return any information: > [tux@server1 ~]$ sudo sshd -T server2 \> server2\_output2 > [sudo] password for tux: > Extra argument server2. > > [tux@server1 ~]$ ls -ltr > total 1669924 > -------------Output Cut-------------------- > -rw-rw-r–. 1 tux tux 3536 Dec 11 22:18 server2\_output > -rw-rw-r–. 1 tux tux 3536 Dec 11 22:22 server1\_output ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 11, 2021, 10:38pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/14 "2021-12-11T22:38:25Z")
I was hoping you’d say that regarding the learning part. 😀 I’ve always hated letting something go until I’ve figured out the root cause, and now that I’m retired and have time to burn, I can afford to do so… Back to the issue: we’re running the demon here " ssh_d_ ", not the client “ssh”, so it doesn’t take a host name, just that “-T” argument: ```auto [tux@server1 ~]$ sudo sshd -T > server1_config ``` Try running it without redirecting the output ‘sudo sshd -T’ and you’ll see it spew all sorts of stuff when it works properly. ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 12, 2021, 6:29pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/15 "2021-12-12T18:29:47Z")
Here is what I have got: > ## [tux@server1 ~]$ diff server1\_config server2\_config 14c14 \< permitrootlogin yes > > > permitrootlogin no > > 78c78 > > \< authorizedkeysfile .ssh/authorized\_keys > > * * * > > > authorizedkeysfile /root/.ssh/authorized\_keys Weird thing is on server2, if I do to “vi /etc/ssh/sshd\_config” and check the “autorizedkeysfile” it says “~/.ssh/autorized\_keys” can’t remember if I change this before: ```auto # The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2 # but this is overridden so installations will only check .ssh/authorized_keys AuthorizedKeysFile ~/.ssh/authorized_keys ``` ---
**Author:** ![hulxmash](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/h/e9c0ed/32.png) [@hulxmash](https://community.learnlinux.tv/u/hulxmash)\ **Post date:** [December 12, 2021, 7:08pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/16 "2021-12-12T19:08:44Z")
This shouldn’t affect your ssh connection unless you are trying to use an authorized\_keys2 file. If you are anything like me then, it’s probable that you removed the comment on this line to ensure that authorized keys were being used when you were troubleshooting the ssh connection issues. Is there any chance you have misplaced any settings in the /etc/ssh/ssh\_config file by mistake? It’s looking more and more like it’s a client side connection issue to me. If that’s not it. Try running the sshd in debug mode using a different port by running /usr/sbin/sshd -d -p 2222 on server2. Watch the output when you try to connect from server1 using ssh -p 2222. You should be able to see the public key “handshake” and what went wrong. ---
**Author:** ![efahl](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/e/58956e/32.png) [@efahl](https://community.learnlinux.tv/u/efahl)\ **Post date:** [December 12, 2021, 7:27pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/17 "2021-12-12T19:27:44Z")
That `/root` is probably just because of the `sudo`, if it were possible to run it as user `tux` it would probably be `/home/tux/.ssh/authorized_keys`, so I don’t think that’s an issue. @hulxmash Yeah, I’ve been thinking it’s a client side issue for a while, too, good tips there. ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 13, 2021, 9:16am UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/18 "2021-12-13T09:16:38Z")
As per instruction I have ran server2 using “sshd -d -p” > [tux@server2 ~]$ sudo /usr/sbin/sshd -d -p 34627 > debug1: sshd version OpenSSH\_7.4, OpenSSL 1.0.2k-fips 26 Jan 2017 > debug1: private host key #0: ssh-rsa SHA256:ssb4fn3UAtflCtBLI3N5H5hSXI+Z7KQ6CPguMlAzoNA > debug1: private host key #1: ecdsa-sha2-nistp256 SHA256:oV4f6EICfpOJ4YYf7KIWxq8Ga3yPj/6VSBX0yFXG3Uk > debug1: private host key #2: ssh-ed25519 SHA256:1OR73+mSppNAjAoEVLC6vhFl40/e7Py23TdT/MFHXpI > debug1: rexec\_argv[0]=‘/usr/sbin/sshd’ > debug1: rexec\_argv[1]=‘-d’ > debug1: rexec\_argv[2]=‘-p’ > debug1: rexec\_argv[3]=‘34627’ > debug1: Set /proc/self/oom\_score\_adj from 0 to -1000 > debug1: Bind to port 34627 on 0.0.0.0. > Server listening on 0.0.0.0 port 34627. > debug1: Bind to port 34627 on ::. > Server listening on :: port 34627. When I try to connect via ssh coming from server1, I got this output: > debug1: userauth-request for user tux service ssh-connection method publickey [preauth] > debug1: attempt 1 failures 0 [preauth] > debug1: userauth\_pubkey: test whether pkalg/pkblob are acceptable for RSA SHA256:Ji1d4762rLaxsP8JZ070JQYjVtBAkcQ8r5Kr/mbcy9g [preauth] > debug1: temporarily\_use\_uid: 1000/1000 (e=0/0) > debug1: trying public key file /root/.ssh/authorized\_keys > debug1: Could not open authorized keys ‘/root/.ssh/authorized\_keys’: Permission denied > debug1: restore\_uid: 0/0 > Failed publickey for tux from 192.168.10.243 port 57974 ssh2: RSA SHA256:Ji1d4762rLaxsP8JZ070JQYjVtBAkcQ8r5Kr/mbcy9g What I did is delete the .ssh directory under root’s home directory and then went to /etc/ssh/sshd\_config and edit the entry under “authorizedkeysfile” back to “.ssh/authorized\_kerys” This addressed my issue. Thank you so much for the help. ---
**Author:** ![hulxmash](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/h/e9c0ed/32.png) [@hulxmash](https://community.learnlinux.tv/u/hulxmash)\ **Post date:** [December 13, 2021, 4:27pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/19 "2021-12-13T16:27:44Z")
I’m glad you got it working. This was a good one to learn. Thanks for sharing. ---
**Author:** ![adelaide-Guy](https://community.learnlinux.tv/letter_avatar_proxy/v4/letter/a/b4bc9f/32.png) [@adelaide-Guy](https://community.learnlinux.tv/u/adelaide-Guy)\ **Post date:** [December 13, 2021, 6:03pm UTC](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256/20 "2021-12-13T18:03:09Z")
Thank you for sharing that debug command without it I won’t be able to address my issue and thank to @efahl for providing information that help me understand on how I can troubleshoot ssh connection issue. [Next page](https://community.learnlinux.tv/t/public-key-authentication-getting-errors/1256.md?page=2)