Solved

How do I see man for /etc/ssh/sshd_config file?

Posted on 2016-08-29
4
68 Views
Last Modified: 2016-09-01
I am interested in options to disable remote root access.
I want to know what does these lines mean:

# Authentication:
LoginGraceTime 120
PermitRootLogin without-password
StrictModes yes

Open in new window

System: Debian GNU/Linux 8.5
0
Comment
Question by:Taras Shumylo
4 Comments
 
LVL 68

Accepted Solution

by:
woolmilkporc earned 125 total points
ID: 41774563
man sshd_config

If you need further assistance please let us know.
0
 
LVL 11

Assisted Solution

by:andreas
andreas earned 125 total points
ID: 41774568
man sshd_config is working on my distro.

root login only with authentication methods other than password

strictmodes logins only if file permissions on the necessary files are as expected. No others than user should be able to edit.
0
 
LVL 24

Assisted Solution

by:Dr. Klahn
Dr. Klahn earned 125 total points
ID: 41774569
I think you'll find this satisfactory:


# Authentication:
LoginGraceTime 15
PermitRootLogin no
StrictModes yes

Open in new window


Line 1:  Reduces the time allowed to log in to 15 seconds.  Most users should be able to type in their username and password within 15 seconds.  If this is too short, increase it as desired.  The default time of one minute is too long imo; it allows denial of service by a hostile using up limited SSH connections but not logging in.

Line 2:  Disables root logins over SSH entirely.  Anyone wanting to SSH in and use root privileges must su or sudo after logging in unprivileged.

Line 3:  "The option StrictModes specifies whether ssh should check user's permissions in their home directory and rhosts files before accepting login. This option must always be set to yes because sometimes users may accidentally leave their directory or files world-writable."

See also this brief discussion of sshd security options.
0
 
LVL 77

Assisted Solution

by:arnold
arnold earned 125 total points
ID: 41775717
You should have an entry, allowrootlogin or permitrootlogin change it to join, restart ssh and it will deny root login via ssh.
As the prior experts, the setting will allow root to login if/when using dsa/RSA keys in authorized_keys2 containing the public key when ssh-keygen -t (dsa|rsa)
I think depending on your version other ciphers might be available using 1024 bit or larger.
0

Featured Post

Comprehensive Backup Solutions for Microsoft

Acronis protects the complete Microsoft technology stack: Windows Server, Windows PC, laptop and Surface data; Microsoft business applications; Microsoft Hyper-V; Azure VMs; Microsoft Windows Server 2016; Microsoft Exchange 2016 and SQL Server 2016.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

SSH (Secure Shell) - Tips and Tricks As you all know SSH(Secure Shell) is a network protocol, which we use to access/transfer files securely between two networked devices. SSH was actually designed as a replacement for insecure protocols that sen…
Secure Shell (SSH) is a network protocol for secure data communication, mainly used to administer remote Unix / Linux servers via command line. But it also allows the user to open a secure tunnel between a client and a server where he can send any k…
Learn how to get help with Linux/Unix bash shell commands. Use help to read help documents for built in bash shell commands.: Use man to interface with the online reference manuals for shell commands.: Use man to search man pages for unknown command…
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.

863 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

22 Experts available now in Live!

Get 1:1 Help Now