06-15-2023 12:04 PM
I know it's old, but I've got 2 48p Catalyst 3750Gs running IOS 15. I've setup SSH on cat switches before without issue but for some reason this one is just being super resistant. I can log in with my user account to the HTTP interface without any issues, but it says login failed for both SSH and telnet. I've generated the rsa keys and whatnot, putty connects just fine, it just always says that authentication failed. It does this with both accounts i've added. Both accounts work fine on HTTP.
version 15.0
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname house-cat3750G
!
boot-start-marker
boot-end-marker
!
no logging console
enable secret 5 [redacted]
!
username [redacted] secret 5 [redacted]
username [redacted] secret 5 [redacted]
aaa new-model
!
!
aaa authorization exec default local
!
!
aaa session-id common
clock timezone UTC -6 0
clock summer-time UTC recurring
switch 1 provision ws-c3750g-48ps
system mtu routing 1500
ip domain-name DOMAIN.com
!
!
!
[interface/crypto key configs removed to save space]
!
interface Vlan99
ip address 10.10.10.1 255.255.255.0
no ip route-cache
!
ip default-gateway 10.10.10.254
ip http server
ip http secure-server
!
!
!
!
!
vstack
!
line con 0
line vty 0 4
session-timeout 28800
password 7 [redacted]
transport input telnet ssh
transport output telnet ssh
line vty 5 15
session-timeout 28800
password 7 [redacted]
transport input telnet ssh
transport output telnet ssh
!
end
06-15-2023 12:16 PM - edited 06-15-2023 12:17 PM
aaa authentication login default local <<- this for telnet
for SSH
you need ip domain-name and RSA before you can access via SSH
https://www.cisco.com/c/en/us/support/docs/security-vpn/secure-shell-ssh/4145-ssh.html
NOTE:- you need username xxx password xxx and enable password xxx before enable auth via aaa
06-15-2023 12:19 PM
Hi, yes I've already done the ip domain-name and RSA.
06-15-2023 12:21 PM
Aaa auth login is missing
06-15-2023 12:25 PM
Ok, I added:
aaa authentication login default local
No change in behavior though.
06-15-2023 12:29 PM - edited 06-15-2023 12:30 PM
Same then try
Add under line vty
Login auth defualt
06-15-2023 12:32 PM
Ok, added that. Still no change in behavior
06-15-2023 12:37 PM
Username xxx previllige 15 password xxx << - add this
06-15-2023 12:42 PM
so after adding the aaa authentication login default local I lost the ability to login via the serial cable (which is why I didn't have that line in the config initially). Switch is rebooting to undo the aaa auth at the moment.
06-15-2023 12:51 PM
Sorry can you elaborate more' how aaa auth effect access via console ?
06-15-2023 01:09 PM
It will prompt for a username and password at the serial connection.
Neither of the usernames/passwords specified will work. I'm not able to leave the username blank and use the enable password.
06-15-2023 01:12 PM
Ok, switch rebooted. I added the aaa authentication line /only/ under vty 0 15. This still doesn't allow login.
I deleted the second user and added a new user:
username admin password 0 admin priv 15
Still unable to login.
06-15-2023 01:21 PM
Just one second'
You can access via console and do config ?
But still can not access via telnet and ssh ?
06-15-2023 01:24 PM
Sorry I missed this reply. Yes, after rebooting the switch (which reverted the aaa auth) I am able to access the console port without credentials and make config changes.
If I add the aaa authentication line back, username/password is required via the serial console and I'm unable to log in due to it not accepting the credentials.
06-15-2023 01:34 PM
aaa need
aaa authentication login default local
NO aaa authorization exec default local
username mhm privilege 15 password mhm
enable password mhm
under the line of vty
login authenation default
NOTE:- please dont copy run to start, in case this config not work you can access via console
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