IE3300 SSH connection

[kchesg]

Hi Everyone,

After replacing the IE3000 switch with the IE3300, the SSH connection stopped working despite identical configurations. However, changing the subnet from 255.255.255.128 to 255.255.255.0 restored the SSH connection. This behavior is quite unusual. The IP address and the computer using SSH remain unchanged with IE3000 & IE3300. Any insights?

[balaji.bandi]

May be some the of the old do not care about mask i have seen this on Windows Server, when the latest come in picture, they fixed most of the known issue, so it will be some kind of stuff what i see here.

what is the Orginal subnet configured as IP ? what is the PC configured in same subnet or you coming from remote IP to connect SSH ?

[kchesg]

Thank You Sir. Your explanation is sounds logical. 
The PC subnet is 255.255.255.0, while the original subnet for the IE3000 was 255.255.255.128. This configuration was also applied to the IE3300. Additionally, the PC is connected to a C3850 with an uplink connection from the IE3000/IE3300. As mentioned, the configuration followed is identical and we just replaced the switch due to its obsolescence. 
 Although, we will able change the subnet to make it work but we are keen to understand this behaviour. 

[balaji.bandi]

The PC subnet is 255.255.255.0, while the original subnet for the IE3000 was 255.255.255.128

If the PC subnet or device subnet different, then what IP address it belong to that subnet is matter here.

if that is not in /25 range of device IP then changing to /24 make sense.

[Leo Laohoo]

conf t
 ip ssh source-interface <MANAGEMENT VLAN>
end
wr

[balaji.bandi]

Source interface only help here if the OP not able to login and configured Management interface.

However, changing the subnet from 255.255.255.128 to 255.255.255.0 restored the SSH connection.

OP confirms changing the subnet mask able to login, so i suspect configuration issue - which need to be match across network.