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6 votes

Bypassing a Cisco Terminal Server Menu

does anyone have experience with these things? Centuries, actually. And that experience says to leave things you know very little (or nothing) about alone, especially when they're systems that (a) ...
Ricky's user avatar
  • 32.2k
6 votes
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Cisco 3750G - SSH Diffie Hellman Group 1 SHA1 Error

Your SSH client is saying "we can't agree on the cipher: server wants X but I'm configured not to speak X". This is a completely general SSH problem, not specifically related to this model of switch, ...
jonathanjo's user avatar
  • 16.3k
5 votes
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Could accessed sites over an SSH tunnel be tracked by ISP?

The DNS is issued by default from your local host, not from the proxy, when using SOCKS (probably because SOCKS4 didn't support other way). Make sure you have checked the checkbox "Remote DNS" in the ...
Jakuje's user avatar
  • 168
5 votes

Telnet or SSH into a Cisco router

You'll need to have a hostname and a domain and generate the keys for ssh to work. My notebook says: hostname gw99 ip domain name example.com crypto key generate rsa modulus 2048 ip access-list ...
jonathanjo's user avatar
  • 16.3k
5 votes
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Can you SSH to a Cisco switch without a Username

You need some sort of credentials for SSH to work. You can either set it up using passwords like normally, or you can use a certificate to authenticate. Here's a discussion that might be helpful: ...
Stuggi's user avatar
  • 2,269
4 votes
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How to fiter non SSH traffic in Wireshark

The ACK packets are not recognised as SSH packets, so the "not ssh" part of your filter doesn't match on them. How about simply using ip.addr == 10.0.0.31 && tcp.port != 22
hertitu's user avatar
  • 2,658
4 votes
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Telnet or SSH into a Cisco router

You can use these commands to set up telnet access ! Set username/password username Lea password Shhh! ! Create standard ACL to control access ip access-list standard ONLY-THESE-GUYS permit 192.168....
Ron Trunk's user avatar
  • 67.6k
4 votes
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Remote access ssh on Ubuntu

Try ssh [email protected] from a computer on a different network. It's likely that your router doesn't have "loopback NAT" (or it has it but it's not enabled), which would explain why you can't ssh to ...
jonathanjo's user avatar
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4 votes
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"ssh: connect to host myserver port 22: Invalid argument" (intermittent, ipv6, link-local address, dhcp hostname)

Whatever is doing hostname resolution is returning link-local IPv6 address(es) that aren't valid for the interface selected -- i.e. "any". Link-local addresses must specify the interface -- eg. fe80:.....
Ricky's user avatar
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4 votes
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CISCO IOS's feature Secure Shell Version 2 Enhancements for RSA Keys

Cisco maintains the Cisco Feature Navigator page where you can look up which features are available for which hardware or OS versions. It doesn't appear that what you are looking for is available for ...
Ron Maupin's user avatar
  • 99.8k
3 votes

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

This works on 2960x software 152-7.E4: ip ssh version 2 no ip ssh server algorithm authentication password no ip ssh server algorithm authentication keyboard line vty 0 15 transport input ssh This ...
Roger Sanghee Gold's user avatar
3 votes
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Configure SSH cipher on Cisco IOS 12.2(55)SE7

As stated by @Teun Vink in comment, no way to do so but the given workaround using ssh -oHostKeyAlgorithms=+ssh-dss -oKexAlgorithms=+diffie-hellman-group1-sha1 $HOST do the trick.
JFL's user avatar
  • 19.7k
3 votes
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Cisco SSH disconnect

[EDIT: updates at bottom] It turns out to be to do with the encryption algorithm, and thus indirectly related to the version of Cisco IOS. The router on the bench is just to help me debug the ...
jonathanjo's user avatar
  • 16.3k
3 votes

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

Well, actually you CAN enable telnet and ssh. It's completely unsupported, but anyway: Update firmware to latest version, I used PD.02.06.stk. Go to Maintenance -> Backup and Update Manage, click ...
Grrruk's user avatar
  • 131
3 votes
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Login local , login synchronous

login local tells the router to use the local database for authentication. You add account to the local database using the username command. logging synchronous (not login synchronous) formats the ...
Ron Trunk's user avatar
  • 67.6k
3 votes
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cisco catalyst creating user fails

The configuration has to include: A hostname (hostname sw99) A domain name (ip domain-name example.com) You have to have generated the keys (crypto key generate rsa) Enable the SSH server (ip ssh) ...
jonathanjo's user avatar
  • 16.3k
3 votes

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

Basically, port forwarding is creating a manual, static entry in the NAPT table. The table will build dynamic entries as traffic is sent from inside to outside (these entries will eventually close or ...
Ron Maupin's user avatar
  • 99.8k
3 votes

What is the point of Junos outbound SSH service?

In Junos, outbound-ssh is used to allow the device to connect back to an external management platform via NETCONF over SSH, allowing remote management of devices that were behind NATs or jump-hosts. ...
Benjamin Dale's user avatar
3 votes
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ssh from cisco with fake source-ip

Make sure router 1 is advertising connected routes to router 2. Create a loopback interface on router 1 with an IP in that range. For example interface loopback 0 ip address 10.64.95.66 255.255.255....
Ron Trunk's user avatar
  • 67.6k
3 votes

How to generate cisco key-hash string

Cisco uses various hashes. Simply search for cisco password hash algorithm , and you will find explanations, such as Cisco Routers Password Types: Cisco Routers Password Types Feb 13, 2020 Knowledge ...
Ron Maupin's user avatar
  • 99.8k
3 votes

Cisco ASA5505/6 - public key authentication does not work with OpenSSH client

The ASA5505/6 units I tested, versions 9.2(4) and 9.8(2), require "ssh-rsa" be among the available signature algorithms for public key exchange regardless of the SSH client software you use. ...
Frobozz's user avatar
  • 171
2 votes

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

Assign an IP to the management interface switch(config)# interface ethernet 2/1 switch(config-if)# no switchport switch(config-if)# ip address 192.0.2.1/8 switch(config-if)# copy running-config ...
Ty Smith's user avatar
  • 533
2 votes

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

I just tested with ASA 9.1.7 and found that telnet and ssh with password authentication works fine with "auto-enable", but ssh with publickey does not. A workaround is to push the enable sequence to ...
CraigW's user avatar
  • 21
2 votes

Nexus OS authenticate via ssh key

In NX OS version 6 the following works: username <your username> sshkey ssh-rsa <your rsa key> You must of course set the access level with, for example for full access username <...
JFL's user avatar
  • 19.7k
2 votes

Alcatel OS6860E ethernet ssh

You missed the vlan NNN statement at the end of the last line. Your vlan_99_ip is the mnemonic name of the L3 switch interface. It can't be assigned to the vlan 99 automatically. You config should be ...
Avalerich's user avatar
2 votes

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

Eddie's answer is 100% correct. I just want to add that you can also use this technique: Router(config)# username teddy password teddybear Router(config)# aaa new-model Router(config)# aaa ...
OzNetNerd's user avatar
  • 2,337
2 votes

JunOS ssh debugging

Unfortunately there are no traceoptions for SSH that I'm aware of. If you have access to a *nix machine with your SSH keys loaded, you could try connecting with: ssh -vvv user@router and see which ...
Benjamin Dale's user avatar
2 votes
Accepted

Cisco TACACS authentication config

The config you've posted is pretty common, and I suppose it was developed to be as flexible as possible, with separate methods for VTY and console access, as well as separate command authorization for ...
Ron Trunk's user avatar
  • 67.6k
2 votes
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How does a network switch affect SSH?

SSH is an application protocol running on top of layer 4 TCP. A switch basically works at layer 2, so it doesn't affect SSH at all (unless it has higher layer features that do affect IP, TCP or even ...
Zac67's user avatar
  • 84.8k

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