Questions tagged [ssh]

Secure Shell or SSH is a network protocol that allows secure communication. For most it is a preferred alternative to Telnet when available. SSH can use automatically or manually generated keys for authentication.

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25
votes
9answers
18k views

Why use SSH and VPN in combination?

My employer requires me to first log on to a VPN, and only then I can SSH into the servers. But, given the security of SSH, is a VPN overkill? What is the use of a VPN in terms of security if I am ...
16
votes
3answers
10k views

Backing up Cisco router configuration - including ssh keys

We have some Cisco 2821, 2921 and 1921 routers in our shop. I can back up and restore the configurations by copying out or in the startup-config file, but what about the keys for ssh? I don't want ...
14
votes
3answers
16k views

how to block ssh tunneling traffic?

if someone were to set up an ssh tunnel to/from work or home, is there a way to prevent future SSH tunneling traffic? I understand that websense can block traffic, but users who use ssh tunneling can ...
11
votes
1answer
5k views

Cisco IOS built-in SSH client default version

You issue the command ssh 192.168.97.97 from a IOS device and the destination IOS router/switch SSH server is accepting both SSH versions. Being that you did not specify a version to use on the SSH ...
10
votes
1answer
7k views

Authenticate ssh key via Cisco ACS (TACACS+)

I can set a router to authenticate via a ssh public-key with: ip ssh pubkey-chain username admin key-string <ssh-pub-key> exit exit Is it possible to do something similar with Cisco ...
9
votes
3answers
7k views

Cisco can't connect to Juniper device via SSH - Invalid modulus length

I'm trying to connect from a Cisco 886VA to a Juniper EX2200 via SSH. The connection fails with the following messages on the Cisco: *Jan 17 09:51:20.823: SSH2 CLIENT 0: Server has chosen 2056 -bit ...
7
votes
3answers
3k views

Is the Nth ports on 127.0.0.1 and 127.0.0.2 same ?

I want to create ssh tunnels between 2 clients and 1 server. Can I use the same port numbers for both but binding one of them to 127.0.0.1:N and the other to 127.0.0.2:N ? Are these ports same or can ...
6
votes
2answers
5k views

Does anyone know how to import ssh public key to ASR9K (IOS-XR)?

I am trying to login ASR9001 router using ssh public key authentication. I tried to import my ssh public key to the router but no success. RP/0/RSP0/CPU0:ASR9K-1#crypto key import authentication rsa ...
6
votes
2answers
4k views

What is the OID needed to generate a ssh crypto key on a Cisco switch or router running IOS using snmpset?

I have a few routers and switches that were deployed to remote locations and the crypto key was not generated before they were shipped, they are working and I have SNMPv3 write access to them but I ...
5
votes
2answers
8k views

Why do I get a timeout when I connect via ssh to a Cisco ASA, even though management and ACLs are configured?

I set up a Cisco ASA 5505 8.4(3), and specified ssh version 2 enabled ssh access to the WAN interface via ssh <my network> <mask> <WAN interface> allowed ssh from my network via an ...
4
votes
1answer
269 views

Cisco switch generates two pairs of keys

The problem is: I generate a key pair on a switch and when i use: show crypto key mypubkey rsa it shows two keys. A geral-purpose key and an encryption key. The general-purpose key is the key i ...
4
votes
1answer
155 views

CISCO IOS's feature Secure Shell Version 2 Enhancements for RSA Keys

I have a switch C3750V2-48PS with IOS ver. 12.2(55)SE5. I wanted to copy to it public key for the ssh client but I do not have following command available Switch#configure terminal Switch(config)#ip ...
4
votes
3answers
3k views

How to install SSL key and certificate on SG 300-10 (and SSH functionality)

How to install our own SSL key and certificate on a SG-300-10 switch? The manual simply doesn't seem to bear much resemblance to what's available in the web interface. According to the manual, one ...
3
votes
2answers
14k views

Telnet or SSH into a Cisco router

I would like to log into a Cisco router that is in a LAN via telnet or ssh as user <username> with a password <password> only from machines in the LAN 192.168.2.0/24 About the user: I ...
3
votes
2answers
3k views

How do I set up secure remote access to my home lab network?

My current setup is the following: ATT ISP ---- ATT wireless router ---- cisco 890 wireless router My cisco 890 is for internet and remote VPN access from home to my company, however, I don't have ...
3
votes
4answers
10k views

Switches 'HPE OfficeConnect 1920S' - Enable SSH / TFTP Services

We need to manage switches HPE OfficeConnect 1920S remotely but only HTTP/HTTPS Administration is available. HPE 1920S has an special operating system, neither Procurve nor Comware. We are looking ...
3
votes
1answer
4k views

How to specify username for SSH in Juniper router?

Model: ACX2200 Version : 15.1X54-D10.5 I have two Juniper routers connected back-to-back , first router is enabled with TACACS login. Second router is not enabled with TACACS login yet. So to ...
3
votes
2answers
174 views

Why http + ssh is not popular? [closed]

Can HTTP be used with SSH ? If yes, why has it not been as popular as HTTP over SSL ?
3
votes
1answer
1k views

Could accessed sites over an SSH tunnel be tracked by ISP? [closed]

I created an SSH tunnel and using it as SOCKSv5 proxy on Firefox. I checked whatismyipaddress.com and some other sites, they could not detect a proxy on my computer and shows my location on the server'...
3
votes
1answer
3k views

Can you SSH to a Cisco switch without a Username

Is there a way of setting up a Cisco swtich (Cisco Catalyst 3850 12 Port GE SFP IP Base - its not arrived so I don't know the IOS) to allow SSH without specifying a USERNAME The customer currently ...
3
votes
1answer
3k views

How to detect port changes in real time on Cisco 4506

Is it possible to detect if any cable was connected/disconnected in real time via Telnet session on Cisco Catalyst 4506? For example, I have an IBM Switch EN94093R that does it by default, when I ...
3
votes
2answers
902 views

Domain name for SSH

What is the purpose of a domain name to create SSH keys? Before enabling SSH on firewall/router, we need to create domain name. Why is it necessary to do that? What does a domain name do and how is ...
3
votes
1answer
31 views

In port forwarding, is the ultimate destination decided solely by the intermediary entity?

In port forwarding, is the ultimate destination to connect to solely decided by the intermediary entity which provides port forwarding, not by an application client? Although the page mentions dynamic ...
3
votes
1answer
133 views

Hp procurve 2510 ssh problem

My app connects to switches via ssh to gather info from them. I can connect to any model except this one. I get the authentication error from the switch yet i can connect via putty with the same ...
3
votes
1answer
2k views

How do I auto-enable on an ssh public key login on an ASA?

I am trying to allow an ssh session to auto-enable on my ASA. I am enable to ssh to the asa with the public key and get directly to a non-enabled prompt, but I want that prompt to enter in enabled ...
3
votes
2answers
2k views

Sonicwall - SSH to change admin password

Is it possible to reset a password for the admin account on a Sonicwall via SSH?
3
votes
3answers
2k views

Cisco ASA 5585 SSH LDAP Authentication

I am attempting to setup Microsoft LDAP authentication, for SSH only, for a specific security group on a Cisco ASA 5585 version 8.2(5) using the ASDM. The lookup and authentication is working, however ...
3
votes
1answer
958 views

Port forwarding doesn't work

I'm using an EdgeMAX router. From the GUI, I'm trying to forward the WAN (eth1) port 22 to the LAN (eth2) port 22 to a local IP address (172.16.12.3) to allow SSH from outside my network. When I tried ...
3
votes
3answers
1k views

Can I limit Cisco IOS login to specific users?

I have a Cisco IOS router that is used for WAN access. I have 2 additional users defined with less privilege to check status and to use ssh. I wonder if it is possible to restrict certain user to only ...
2
votes
3answers
11k views

How to assign a static IP to a Cisco Layer 3 switch in order to connect using SSH?

The steps of this manual have been executed in order to configure SSH. Once SSH has been configured, how to access the switch from a computer using SSH? The following steps have been executed in ...
2
votes
3answers
738 views

Bypassing a Cisco Terminal Server Menu

The guys at a config center connect to devices by: placing them on a management rack, and plugging them into a management switch by means of some hwic/RJ45 reverse telnet connection. When you remote ...
2
votes
2answers
1k views

Cisco 3750G - SSH Diffie Hellman Group 1 SHA1 Error

I recently implemented SSH configuration on my 3750G switch stack. I have -set the domain name -generated the rsa key using 2048 bits -ensured that the vty lines are set to transport input ssh Now ...
2
votes
2answers
4k views

How to fiter non SSH traffic in Wireshark

I am trying to monitor behaviour of packets from my PC -> VirtualBox machine which represents a virtual router, and I have established SSH session to it. My question is, how to filter out all SSH ...
2
votes
1answer
128 views

cisco catalyst creating user fails

I took over a couple of Cisco 2960x switches. They are configured with a telnet login. Now that telnet isn't that great (and my colleagues are afraid of CLI but might have to configure things too) I ...
2
votes
1answer
3k views

Cisco SSH disconnect

I have a Cisco 867VAE with 15.5(3)M which is disconnecting from a particular legitimate SSH client with %SSH-4-SSH2 _UNEXPECTED_MSG: Unexpected message type It's on a bench, not in service. I have ...
2
votes
1answer
5k views

Configure SSH cipher on Cisco IOS 12.2(55)SE7

Today a customer contacted me because he has upgraded his MacBook to MacOS X Sierra and since then, when trying to access a switch via SSH he got the message Unable to negotiate with 10.XX.XX.XX ...
2
votes
3answers
7k views

is a vty password requierd if i have login local set with a username and a password

i am trying to configure the switch to have both telnet and ssh. from what i understand the "login local" command will tell the switch to ask for the user name and password i've configured using ...
2
votes
2answers
1k views

How do I I test ip ssh dh min size on two cisco routers?

The requirement is that when DH min size is set to group 14 (2048) a session using DH group 1 (1024) is not allowed How can I really test this requirement on 2 CISCO routers. Do I need to configure ...
2
votes
1answer
761 views

SSH failing from Cisco to Juniper - SSH2 CLIENT 0: Channel open failed, reason = 1752134516

Not able to SSH from Cisco IOS 15.2(2)E8 to Juniper 14.1X53-D48.1 HOST#show debugging SSH: SSH Client debugging is on HOST#ssh 1.1.1.1 *Feb 11 15:55:47.448: SSH CLIENT0: protocol version id is - ...
2
votes
1answer
630 views

Restrict VTY SSH access to only MGMT VLAN and loopback

For the sake of the fact that i'm not allowed to share actual configuration, every posted config below is made up or altered. We have more than 250 locations spread over our country. All locations ...
2
votes
1answer
40 views

Random intercontinental TCP streams are slow

I have a home server in New Zealand and a remote server in Amsterdam of the following configuration: I have a simple test script: #!/bin/bash for i in `seq 1 20`; do scp root@remoteserver:~/...
2
votes
3answers
686 views

Cisco ISR4450 Router SSH access denied

I configured an ssh connection on an ISR 4451 router, which always worked perfectly. For several weeks, every time I want to connect with Putty via SSH, I get an "access denied". I also cant connect ...
2
votes
1answer
995 views

Cisco IOS public-key auth with privilege 15 and no password

From IOS 15 we can log on Cisco IOS with RSA public key authentication. However we still have to assign a password to the user. If we don't the user can log on without any password (and without the ...
2
votes
2answers
12k views

debug crypto ipsec via ssh

How to debug IP Sec VPN on ASA using SSH? I try debug crypto ipsec terminal monitor logging monitor it asks for completion if i choose debug, all debug info are flooded. How do i view just IPSEC ...
2
votes
1answer
468 views

“port forwarding” in netcat/socat, ssh, and commerical router

I have seen "port forwarding" associated with netcat/socat, ssh, and configuring server inside the local LAN behind a NAT device. Does it have different meanings in the cases? For example does "...
2
votes
3answers
4k views

When using SSH, why it doesn't ask for a username and it's corresponding password?

Here is the running-config for the line vty: line vty 0 4 password 1111 login local transport input ssh line vty 5 15 password 1111 login local transport input ssh However, when I type ssh -l domain-...
2
votes
1answer
86 views

Why are there so many different Network File Systems & File Transfer Protocols? [closed]

I've been spending a lot of time trying to learn different Network File Systems & File Transfer Protocols etc. in order to integrate three different devices with three different Operating Systems: ...
2
votes
1answer
107 views

Cant connect to PC via SSH

I use Windows 7 on my desktop. I tried to connect my Android to my PC via Wi-Fi connection. SSH port 22 is open on my desktop. I use Connectbot to connect to my pc . The result of ipconfig: C:\...
1
vote
1answer
297 views

SSH to Cisco ASA 5505

According to this documentation it should be possible to enable an SSH connection to a Cisco ASA 5505. However, it is not possible to ping an IP from the ASA while this has been configured. As it is ...
1
vote
2answers
37 views

Is there any method for insert ssh key in putty when i need to connect cisco router?

I need to connect to cisco router and use private key to connect, but i need to use to putty for ssh. Is there any way?