Allow only ssh cisco Remove the existing vty Jun 1, 2022 · The suggestion by @Flavio Miranda to use access-class is the traditional approach to controlling who can have remote access. Password: R1> You can also use another Cisco IOS device as a SSH client. 225. In ISE 3. interface vlan X. X , 15. Is there an elegant way of Apr 22, 2008 · All, I have been using telnet for a while now to access my routers now that my routers are configured to use SSH 2 our security group wants us to nix the telnet access all together. local. Apr 1, 2025 · Allow only SSH access on VTY lines using command “transport input ssh”. However I want my users SSH it on management IP only. 1 Password: ***** //type "password_SSH' here R1> “-l” means we will provide the username (“admin” in this case) along with this parameter. As simple as it may be I never have done it. Kindly suggest how to configure this. , 101) that allows only the administrators’ systems to make these connections and apply this access-list to the virtual terminal lines. 1 will also work which obviously we dont want. Aug 10, 2020 · I dont want to accept SSH logins via the main VRF Gig interfaces at all. transport input telnet ssh - will only allow telnet and ssh . 1. Every other ssh connections such as aes192-cbc hmac-sha1 or hmac-md5 will fail. Tha Jul 5, 2024 · Select Allow only listed IP addresses to connect. I can get this to work on a Unix/Linux box in less than 10 seconds. Then, to maintain a secure SSH connection, a crypto key is generated using ‘crypto key generate RSA’ command. 1) and all telnet /SSH access to remaining vlan interface should be restricted. Here is an example: ip access-list extended SSH_ACCESS permit tcp 10. ip access-list extended Manage-SSH. You need to apply it IN direction. This command will allow only SSH access. SSH Version 2 Configuration on a Cisco router IOS. For SSH configuration examples, see the “SSH Configuration Examples” section in the “Configuring Secure Shell” section in the “Other Security Features” chapter of the Cisco IOS Security Configuration Guide, Cisco IOS Release 12. permit tcp host [Remote IP,(yours)] host [swith IP] eq 22 . From client side you can do: ssh -c aes256-cbc -l -m hmac-sha1-160 -l . Create an administrator user with cisco as the secret password. Apr 26, 2023 · Phase: 1 Type: UN-NAT Subtype: static Result: ALLOW Config: nat (Inside,WAN) source static SSHServer SSHServer_ExternalNAt Additional Information: NAT divert to egress interface Inside(vrfid:0) Untranslate 176. Telnet accesses will be rejected. Anyone know how to do this Jan 25, 2010 · You only have 2 options for SSH server support on IOS, per the documentation: SSH server and SSH client are supported on DES (56-bit) and 3DES (168-bit) data encryption software images only. But it also allows some other protocols (they are not common in today's networking environment - but the original question was quite specific that they want to allow only 2 protocols and not all protocols). By enabling SSH and configuring this transport protocol on the VTY lines of the IOS device, it will automatically disable Telnet as well. We've got our switches and routers configured for using SSH only to be accessed on the vty lines. Here’s how: Mar 12, 2014 · Hi, I have configured 10 interface vlan on my cisco core switch 6509. hostname R1 aaa new-model username Cisco password Cisco ip domain-name Cisco. Here is an example of the whole thing put together (access-list and vty line config). Does this look like a clean way to do this? ip access-list extended SSH_ACCESS permit udp Management VLAN ip any eq 22 permit tcp Management VLAN ip any eq 22 Jan 29, 2010 · Hi Guys I've set up ssh on my 3925 router and I would like to allow ssh access from only one physical interface. 4. Encryption keys are not used for telnet sessions, only for ssh. (ie: users from any network able to ssh /telnet access to 192. Configure the VTY lines to check the local username database for login credentials and to only allow SSH for remote access. By using access-class under line vty. 1 you do not have an option to select bewteen Admin and User services, enabling IP Access Restriction blocks connections to: GUI; CLI; SNMP; SSH; A dialog box opens where you enter the IP addresses, IPv4 or IPv6, in CIDR format. ip ssh rsa keypair-name sshkey Feb 25, 2025 · The suggestion from Leo would certainly allow both telnet and SSH. In 3DES software images, both DES and 3DES encryption algorithms are available. transport input telnet = will only allow telnet . 99, you still have SSHv1 allowed. I only want remote SSH via GIG 0, the mgmt interface & configured MGMT VRF. Switch9k(config)# ip ssh version 2 Mar 21, 2024 · I want to be able to make SSH connection to the switch, but only from a single host on the internal network, blocking all other connections, whether external or internal. but . 168. The following example shows the configuration of the first three steps: Router(config)#hostname R1 R1(config)#ip domain-name cisco R1(config)#username study password ccna R1(config)#crypto key generate rsa The name for the keys will be: R1. Allow only SSH connections to these lines by using the transport input ssh command. Using IOS as example: ip access-list extended ssh-acl remark match incoming ssh traffic to vlan 20 SVI deny tcp any 20. SSH access on other IP (defined for each interface vlan) should be blocked by switch. IP Access configuration. The only thing you have to do is to select the SSH protocol, enter the IP address and leave the default port at 22: You will see this on the putty console: login as: admin Using keyboard-interactive authentication. Communication between the client and server is encrypted in both SSH version 1 and SSH version 2. In DES software images, DES is the only encryption algorithm available. Dec 23, 2015 · Hi, I try to filter ssh connections to our routers, to permit the access only to specific router IP adresses and tried the following example configuration: access-list 111 permit ip any 10. b. Yes! we can now SSH to R1! 2. deny tcp any any eq 22. I have tried an ACL blocking SSH and applying it to an outside WWW facing interface but trouble is it block all port 22 traffic flowing through the int Jul 17, 2009 · I want to configure the router so that it only accepts ssh version 2 connection with aes256-cbc hmac-sha1. allow only SSH access. Is it possible to specify this kind of thing ? Thanks a lot. 12. Oct 24, 2020 · Hi, Deploy control plane policy to restrict the control plane traffic designed to the device itself. Firstly, we will go to line mode and configure SSH for 16 users from 0 to 15. However, I am struggling to get this to work in IOS routers. 255 any eq 22 line vty 0 2 access-class SSH_ACCESS in line vty 3 4 Enable SSH on Cisco Routers/Switches. And then we will use “transport input ssh”. 0 0. cisco Choose the size of the key modulus in the range of 360 to 2048 for your Aug 26, 2016 · Hi Chris, Make sure to enter the vty line config mode (line vty 015) before applying the access-class command. ip access-group Manage-SSH in. 255 log access-list 111 deny ip any any log! line vty 0 3 access-class 111 in transport input ssh 4. I have created this acl and applied it to vty 0 4 and vty 5 15: ip access-list extended manage-SSH permit tcp 192. transport input ssh - will allow only ssh . On R2 we can use the “ssh” command to SSH to R1: R2#ssh -l admin 192. 183/22 Phase: 2 Type: ECMP load balancing Subtype: Result: ALLOW Config: Additional Information: ECMP load Aug 22, 2013 · From the switch, if you do ‘sh ip ssh’, it will confirm that the SSH is enabled on this cisco device. May 20, 2013 · Hi, we are creating a remote site with several VLANs. And my understanding of the original post suggests that they are probably already doing this "at the moment we've a standard ACL configured for limiting source addresses who can access core switch through ssh, in addition to that we wanted only one of the SVIs to be Hello, Just a quick question if you don't mind. At first, domain name is set using ‘ip domain-name domain-name command. Vendor: Cisco Title: How to allow SSH only to Cisco device Software: 12. Thanks in advance. ssh -c aes256-cbc -l admin 192. Hope Aug 13, 2018 · we need to allow only SSH /Telnet access to Management Vlan interface (192. If you run the “show ip ssh” command and it reports 1. 255. 255 eq 22 remark match all other incoming ssh traffic permit tcp any any eq 22 class-map SSH match access name ssh-acl policy-map CoPP class SSH drop class class May 31, 2024 · Most Cisco switch software images will still allow SSH version 1 by default. CiscoDevice# config terminal Dec 30, 2015 · There are two ways to limit SSH connection. xx/22 to 10. I’m quite surprised you can't force this on server side. myswitch# sh ip ssh SSH Enabled - version 1. a. 20. We want to change this to only allow SSH version 2 as it is more secure. 2- John mentioned it. Step 2 – Generate RSA key to be used. Cisco routers also support a simple SSH client via CLI so we can connect to R1 easily. ssh -c 3des -l admin 192. xx. Best Regards, Nicolas Jun 10, 2009 · To restrict SSH access to the switch, configure an extended access-list (e. if you miss-configure something, you will not be able to login. Jun 11, 2013 · Hi, I want to create an access-list that will allow any host to ssh to the Management address of a switch but, only the Management address. Aug 16, 2021 · SSH Command Execution – All the commands used to enable the SSH is highlighted in the below-provided screen-grab of the Cisco Packet Tracer. So lets see how to enable SSH. Jul 17, 2009 · And yes SSH v2 also works with 3des which is quite weak encryption. 99 Authentication timeout: 120 secs; Authentication retries: 3 After the above configurations, login from a remote machine to verify that you can ssh to this cisco switch. Here, we will do the SSH configuration in line mode. X Platform: Catalyst switches, Routers. x 0. Problem is about default settings of transport input;. The main configuration step of this Configuring SSH lesson is this step. 1-The way you are trying to do. Click Add. 99. Feb 13, 2020 · Step 2: Create an SSH user and reconfigure the VTY lines for SSH-only access. 1). Secure Shell (SSH) is a protocol used when one wants to have vides a secure remote access connection to network devices. Switch9k(config)# do show ip ssh | i SSH SSH Enabled - version 1. 0. 255 any eq 22 deny tcp any any eq 22 The most common SSH client is probably putty. example . 127. g. Step 1-Configure Hostname and DNS Domain. Can anyone instruct me on how to totally turn off telnet on a router. x. First you need to generate SSH keys and then enable SSH transport on VTY lines. We want to create a Management VLAN for the new site and only want management through that Management interface but, we want to get away from creating an access-list blocking SSH, Telnet to the other VLAN interfaces. S1(config)# username administrator secret cisco. jelzz fsmkam mitpyb sbqi grihjwd zeodyca xlous tnyq ogvqzc serbnqf keubv tnnxo yeolhb phuajv pgcdr