GS1910-24: Can't access switch web management or CLI

WmWallberg

We are a small manufacturer who runs several GS1910-24 switches.  We used them for our building backbone to carry from the front to rear of the facilities (approx 75 yards).  Recently I haven't been looking at the switches (it's nice when everything is running well).  However I am trying to track down some overall latency and when I attempted to log into the GS1910-24's I was unable to.  Using my web browser I get 'This site can't be reached'.  This is for each of the managed switches which are running on IP's 192.168.1.200 - .204.  I decided to dig deeper, brought in my laptop to attempt to SSH or Telenet directly into any of these switches.  On my laptop I manually configure and IP of 192.168.1.99, plug directly into a port on a switch and use Putty.  Each time I get a connection refused or a connection timed out error.  I'm looking for some way to access these devices to attempt to determine what is happening.  Does anyone have any thoughts?

Zyxel_Derrick

Hi @WmWallberg

May I know the management VLAN of Switch?
Is it VLAN 1 or have you ever changed management VLAN?
Also, can you access switch by using console cable?

Regards,
Derrick

WmWallberg

I've never setup any VLAN on the switch.  I've always just managed the switch via a browser to it's configured IP (for these switches that is 192.168.1.200 - .204).  I also attempted to log into the console via a serial cable and putty but I got no feedback from the connection.

Sakura_T

Are the switches still forwarding traffic apart from the management? Make sure you choose the right baud rate (9600/115200) when using the console cable. I would suggest rebooting the devices if you've checked everything to see if any improvement.

WmWallberg

The switches are forwarding traffic.  I've hesitated to reboot for fear it worsens the situation.  But a reboot looks like the only option I've got left.  I'll wait for the weekend to decrease the problem of user interference.

Zyxel小編 Lucious

Hi @WmWallberg

1. 
Have you tried another console cable on the switch? Moreover, have you tried to use the console cable on another switch(device)?  You may do some swap test to see if the cable really works.
2. 
Is your OS Win10? We've been reported certain cases with Win10 driver compatibility issue on the (USB to RS232) console cable. You can try different driver to see if it works.
https://www.dropbox.com/s/u2y07mv78i4m5db/PL2303_Prolific_DriverInstaller_v110.exe

Hope it helps.
Zyxel_Lucious

Lacquerhead

I ran into the same problem before with my GS1910-24's.  ZyXel support was less than useful.  The only resolution was to reboot the switch.  Like you, no web, no SSH, only serial console worked.  There were only a handful of firmwares ever released, the most recent from 2014.  This switch has obviously been abandoned by ZyXel and I responded in kind by abandoning ZyXel and getting Cisco SG300 switches instead.

As ZyXel_Lucious alluded to, the Prolific PL2303 chipset has been counterfeited extensively.  A couple years ago Prolific released a new driver which Microsoft distributed automatically.  That new driver identifies the counterfeit chips and simply refuses to pass any traffic.  I've since moved to FTDI based USB-Serial adapters.

Zyxel小編 Lucious

Hi @WmWallberg,

We had an internal discussion about the case.

GS1910 is a L2 switch which packet is forwarded by hardware not by CPU.
Based on your description, this issue may be related to Switch's CPU and in this case it will not impact traffic forwarding.
Since GS1910 is a legacy product from Zyxel and has been out of warranty period, we recommend simple steps for troubleshoot.

Reboot to see if you can login to the Switch successfully. At this time, we suggest you to configure  "Security -> Switch -> Access Management" to block untrusted IP from accessing the switch to protect your Switch CPU.  (In general,  CPU may be affected by large amount of  packets with destination address to itself. ) Please refer the snapshot as below.



If the problem still exists after reboot, then this is very likely that CPU has been defective after years of use.
You may want to consider Zyxel new Switches that supports more extensive security features which offers better protection to Switch CPU and to your network.

Sincerely,
Zyxel_Lucious

sanyvrbovec

hi, 
I have the same problem. my web interface doesn't work. I can access via rs232 port. I reset the switch there but the web interface still doesn't work

sanyvrbovec

sanyvrbovec said:

hi, 
I have the same problem. my web interface doesn't work. I can access via rs232 port. I reset the switch there but the web interface still doesn't work

I finally solved it ... no reset helps. playing by security settings I solved the problem

DIK

@ sanyvrbovec

which security settings did you change?

Regards