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Forum Discussion

htagawa's avatar
htagawa
Guide
Aug 18, 2026

Does CESMB-7607 fix the M4300 CPU spike and loss of Web/SSH access after 120 days

Hi,

 

I have two M4300 switches in production: one 48-port model and one 24x24F model.

After upgrading the firmware from 12.0.19.4 to 12.0.19.15, I started experiencing the following issues.

However, these issues do not occur immediately after the firmware upgrade. They tend to start appearing after approximately 120 days of continuous operation.

 

CPU utilization becomes extremely high.

The switch unexpectedly reboots.

Web UI access becomes unavailable.

SSH access also becomes unavailable.

 

I found the following community post, which appears to describe very similar symptoms:

https://community.netgear.com/discussions/business-managed-switches/m4300-stack-xsm4335fs--gsm4328s----web-ssh-and-snmpv3-all-stopped-working/2476209

 

I also noticed that firmware 12.0.19.23 includes a bug fix listed as CESMB-7607:

https://kb.netgear.com/000070890/M4300-Firmware-Version-12-0-19-23

 

Based on the description of CESMB-7607, I would like to confirm whether this fix is related to the issue described in the community post above.

In particular, does CESMB-7607 address the issue where CPU utilization gradually becomes very high and Web/SSH (and potentially SNMP) access stops working after approximately 120 days of continuous operation?

The fact that the issue appears only after a long period of continuous operation makes me wonder whether there is some kind of resource leak or other long-term stability issue involved.

 

If anyone from NETGEAR, or anyone who has experienced the same issue, could clarify what CESMB-7607 specifically fixes and whether it is intended to address these symptoms, I would greatly appreciate it.

 

Thank you.

2 Replies

  • Hi,

     

    I have two M4300 switches in production: one 48-port model and one 24x24F model.

    After upgrading the firmware from 12.0.19.4 to 12.0.19.15, I started experiencing the following issues.

    However, these issues do not occur immediately after the firmware upgrade. They tend to start appearing after approximately 120 days of continuous operation.

     

    CPU utilization becomes extremely high.

    The switch unexpectedly reboots.

    Web UI access becomes unavailable.

    SSH access also becomes unavailable.

     

    I found the following community post, which appears to describe very similar symptoms:

    M4300 Stack (XSM4335FS + GSM4328S) -- Web, SSH, and SNMPv3 all stopped working

     

    I also noticed that firmware 12.0.19.23 includes a bug fix listed as CESMB-7607:

    - Fixes the issue where gradually increasing memory usage could cause the switch to reboot after extended runtime. [CESMB-7607]

     

    Based on the description of CESMB-7607, I would like to confirm whether this fix is related to the issue described in the community post above.

    In particular, does CESMB-7607 address the issue where CPU utilization gradually becomes very high and Web/SSH (and potentially SNMP) access stops working after approximately 120 days of continuous operation?

    The fact that the issue appears only after a long period of continuous operation makes me wonder whether there is some kind of resource leak or other long-term stability issue involved.

     

    If anyone from NETGEAR, or anyone who has experienced the same issue, could clarify what CESMB-7607 specifically fixes and whether it is intended to address these symptoms, I would greatly appreciate it.

     

    Thank you.

    • natasha052gand's avatar
      natasha052gand
      Aspirant

      I’m running two NETGEAR M4300 switches (one 48-port model and one 24x24F). After upgrading from firmware 12.0.19.4 to 12.0.19.15, I started seeing stability problems, but only after around 120 days of continuous uptime.

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