Zyxel NebulaFlex Switch XGS1935 Series

V4.90(ACJ_.1)C0 Release Note

Date: Aug. 8, 2025

Introduction

This document describes the features in the XGS1935 series for its 4.90(ACJ_.1)C0 release. XGS1935 series is a hybrid switch with NebulaFlex technology to support operation in either Standalone mode or Nebula cloud management mode.

Supported Platforms

Support Platform	ZyNOS Firmware version	Boot Version
Zyxel XGS1935-28	V4.90(ACJW.1)C0	V1.00 \| 05/30/2024
Zyxel XGS1935-28HP	V4.90(ACJX.1)C0	V1.00 \| 05/30/2024
Zyxel XGS1935-52	V4.90(ACJY.1)C0	V1.00 \| 05/30/2024
Zyxel XGS1935-52HP	V4.90(ACJZ.1)C0	V1.00 \| 05/30/2024

New Feature and Enhancements

None

Bug Fixes

Bug Fix Description	Nebula	Standalone
[eITS #240501702] Fixed device IP address and uplink usage are not displayed correctly on Nebula.	✔️	-
[eITS #241100262] Cannot clear classifier names longer than 10 characters.	-	✔️
[eITS #241100288] MSTP root guard cannot prevent the RSTP-superior switch from preempting the Root.	-	✔️
[eITS #241100538] Fixed special characters (space, ' , " ) can be allowed in username to cause configuration error.	-	✔️
[eITS #241200595] Fixed high CPU usage triggered by client switching between trunk interfaces.	✔️	✔️
[eITS #250100026] Fixed abnormal crash issue when continues queries OID 1.0.8802.1.1.2.1.5.4795.1.2.1.1 and its sub-OIDs.	✔️	✔️
[eITS #250100440] Fixed that truncated DNS packets cannot be process to cause DNS parsing failed.	✔️	✔️
[eITS #250201088] When the RADIUS server does not provide a session-timeout attribute, the switch will re-authenticate successfully connected devices every hour by default.	✔️	✔️
[eITS #250200357] The switch has dropped the EAPoL unicast packet.	✔️	✔️
[eITS #250302409] Fixed the device sometimes fail to connect with Nebula server.	✔️	-
[eITS #250500429] Fixed crash when receiving IPv6 tunnel packet.	-	✔️
[eITS #250500683] Voice VLAN (via LLDP MED) does not work properly when enabling MAC-auth under NCC cloud authentication.	✔️	✔️
[eITS #250601084] Fixed hang when using CLI "show tech-support".	✔️	✔️
[eITS #250601569] When the default gateway is configured with a link-local address, the IPv6 routing table may display abnormal/incorrect information for the next hop.	-	✔️
[eITS #250301742, 250600412] Supplicants that have successfully passed 802.1X authentication may still be incorrectly assigned to guest VLAN if the reachability of RADIUS server is unstable.	-	✔️

Known Issues

Known Issue Description	Nebula	Standalone
The switch cannot access cluster member when cluster member's password been encrypted.	-	✔️
The accuracy of cable diagnostic is +- 20m. When without cables, the value of distance to fault would not be 0.	✔️	✔️
Only 2 criteria of link aggregation can be used at the same time. The third criteria set on trunks will not be implemented, but follow the first criteria.	-	✔️

Limitation of Settings

Limitation of Setting	Nebula	Standalone
802.1Q Static VLANs	1K	1K
Static MAC forwarding entry	256	256
MAC filtering entry	256	256
Cluster member	-	24
Port-security max address-limit number	16K	16K
Syslog server entry	2	4
MAC table	16K	16K
Multicast group	1K	1K
ACL	128	256
DHCP Relay Entry	16	16
Static ARP entry	-	256
Static route max entry	32	32
Trunk groups	28(HP):12	28(HP):12
Per trunk group port number	52(HP):24	52(HP):24
MSTP instance	8	8
Voice VLAN OUI entry	-	0-16
ZON neighbor per-port maximum clients	6	10

Change History

V4.90(ACJ_.0) | 07/10/2024
V4.90(ACJ_.1) | 08/08/2025

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