Visit The New, Modern Unix Linux Community


Securing remote connections


 
Thread Tools Search this Thread
Operating Systems Linux Securing remote connections
# 1  
Securing remote connections

Hi all,

I have a couple of questions I've been searching on internet but I didn't find a suitable solution. The aim is that I'd like to access to my home Linux (an 8.04 Ubuntu) from outside. I already achieved with ssh, but I'd like to secure as much as I can. These are questions:
  1. The account I use to login is a sudoer user. So, I want to connect with an unprivileged user, and then, only if I need, reconnect with that user inside my linux. I'd like to disable that account (root is always disabled) from remote connections. How can I do that? or Where can I find some information to disable that account from remote connections?
  2. One of places I'd like to connect is from office, which has a proxy to connect to a computer out of LAN. Almost all ports are disabled. I'd like to know a way to find out which ports are open, to open in my own home the right one (a port also open in office proxy). I thought using "nmap" or "nc" to my own Linux, but it also has almost all ports closed. So connection is not possible unless I open all ports in my router, which is quite dangerous. Using nc or nmap I won't be able to know if a 'connection refused' is because my router has a certain port closed or because port in office proxy is close.
    For example I opened port 443 in my router which redirects to port 22 to my linux. I used this port, because I guessed HTTPS port was available in office proxy. I got right. However, this port is very used and I don't like to leave that port open at home.
Because of my english I don't know if my explanation is good enough, sorry Smilie Any help will be very appreciate.

Thanks
# 2  
Quote:
Originally Posted by AlbertGM
The account I use to login is a sudoer user. So, I want to connect with an unprivileged user, and then, only if I need, reconnect with that user inside my linux. I'd like to disable that account (root is always disabled) from remote connections. How can I do that? or Where can I find some information to disable that account from remote connections?
You can use the AllowUsers directive of sshd_config

Quote:
AllowUsers
This keyword can be followed by a list of user name patterns, separated by spaces. If specified, login is allowed only for user
names that match one of the patterns.
# 3  
Quote:
Originally Posted by Radar
You can use the AllowUsers directive of sshd_config
Thanks Radar,
I'll try it. I hope it makes first question answered!!

Any response in second one?

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #995
Difficulty: Medium
IBM announced its System/370 series in 1970 with full virtualization features.
True or False?

8 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

See AIX server remote connections

Good morning, Is there any command to view remote conxiones an AIX server? Thank you very much and best regards. (1 Reply)
Discussion started by: systemoper
1 Replies

2. AIX

Securing AIX

Guys, i want to securing AIX after install by scratch. Is anybody can inform about the standard port which used by AIX? (4 Replies)
Discussion started by: michlix
4 Replies

3. BSD

Remote connections unable after power falls

Hi everyone: I have a server used for testing running FreeBSD, last weekend we had power cuts in my job and our server was constantly rebooting. since then the network connections are very slow, it's almost impossible establish a remote connection with the server, however running any... (2 Replies)
Discussion started by: edgarvm
2 Replies

4. Cybersecurity

Securing Passwords

Hi All, I'd like to give you an example of what I am trying to achieve and perhaps you might be able to help me along. I would like to add the following criteria to new servers, from a password aging and lockout standpoint. -Number of failed logins before lockout: = 5 -Number of Passwords... (1 Reply)
Discussion started by: mkono
1 Replies

5. Solaris

Unable to open remote connections

Hello everybody, This is an unusual problem that I am facing on my Solaris 9 on Sun Blade 150 workstation. I can ping remote machines (outside subnet) but I can't open up a connection/port on those machines. For example, `ping ftp.xyz.com` gives ftp.xyz.com is alive but if I do a `ftp... (1 Reply)
Discussion started by: red_crab
1 Replies

6. AIX

securing a shell

I would like to secure a shell script from being broken out of with Ctrl-C or equivalent. Once a user logs in, he should not be able to exit to the command prompt. any ideas. Thank you J (1 Reply)
Discussion started by: jhansrod
1 Replies

7. Shell Programming and Scripting

Securing arguments

OK here is my problem. Ive been trying to write a script where i use the order "find". For example if i wont to find some file in the sql_work directory using the script. You use the command: loc sql_work "q*" in order to find all the queries in the directory. Is there any other way to do it,... (0 Replies)
Discussion started by: SolidSnake
0 Replies

8. Cybersecurity

securing a remote box

someone has access to my server... I've got a solaris 7 box with remote access only. many of the services don't have passwords and someone recently messed with the shadow file -the root: line was changed: . password field was changed to NP . the number after that was changed too The... (8 Replies)
Discussion started by: sphiengollie
8 Replies

Featured Tech Videos