If you're deploying Dell EMC Isilon and find one or more nodes stuck in a read-only state with a red battery indicator, you're likely dealing with a common issue related to the NVRAM battery.
This guide walks you through how to diagnose and resolve this issue safely—especially during initial deployments.
Important Disclaimer: This method is not officially supported by Dell EMC for production environments. Use it only during initial setup, particularly if you encounter this issue after powering on the system for the first time.{alertWarning}
🔧 Problem Summary
When the NVRAM battery is not fully charged before powering on the Isilon nodes for the first time, the automatic battery self-test fails. This triggers a read-only state on affected nodes. The system disables battery monitoring until replacement and flags the hardware as unsafe for write operations.
🧭 Step-by-Step Fix
Step 1: Access the Node via SSH
Connect to the node or cluster using SSH:
ssh root@<isilon-node-ip>{codeBox}
Step 2: Check Battery Status
Use the following commands to check the current status of the batteries:
isi batterystatus list
isi batterystatus view{codeBox}
You should see output like:
Lnn Status1 Status2 Result1 Result2
-----------------------------------------------------------------
1 Ready and disabled N/A failed N/A
2 Ready and disabled N/A failed N/A
3 Ready and disabled N/A failed N/A
4 Ready, enabled, and fully charged N/A passed N/A{codeBox}
This means that nodes 1, 2, and 3 failed the test and battery monitoring is disabled.
Step 3: Review Battery Logs
Run this command to verify what the system has logged about the battery:
grep -i battery /var/log/messages | tail -n 50{codeBox}
Example log entries:
isi_hwmon[11777]: Battery 1 Status: Not ready and disabled
isi_hwmon[13535]: Last battery test failed, battery monitoring will not run until the battery has been replaced.{codeBox}
Step 4: Manually Run Battery Test
You must manually initiate a battery test to re-enable monitoring and allow the node to exit read-only mode.
On the current node:
isi_hwmon --battery-test{codeBox}
On all cluster nodes:
isi_for_array -s 'isi_hwmon --battery-test'{codeBox}
On specific nodes (e.g., nodes 1 to 3):
isi_for_array -n 1,2,3 -s 'isi_hwmon --battery-test'{codeBox}
This will start a discharge and recharge cycle.
Step 5: Monitor Battery Status
Re-check the battery status:
isi batterystatus list{codeBox}
You will observe transitions like:
- Discharging
- Charging
- Eventually: Ready, enabled, and fully charged
Keep checking until the status shows that the test has passed.
Step 6: Confirm Battery Test Passed
Check the logs again to confirm the battery passed the test and monitoring is re-enabled:
grep -i battery /var/log/messages | tail -n 50{codeBox}
Expected output:
isi_hwmon[17630]: Battery test passed
isi_hwmon[17630]: Battery monitoring is reenabled following a passing forced battery test result{codeBox}
Step 7: Repeat for All Affected Nodes
Repeat this process for every node that showed a failed battery test. Once all affected nodes have a passing battery status, they should exit read-only mode automatically.
📘 Why This Happens: Initial Power-On Warning
During first-time deployment, if the Isilon nodes are powered on immediately after connecting power, the batteries may not be fully charged. This leads to:
- Battery test failure
- Disabled monitoring
- Read-only node state
✅ Recommendation for New Deployments
Before turning on any Isilon nodes for the first time:
- Connect power cables.
- Quickly force shutdown before OneFS system starts and wait at least 3 hours to allow the batteries to fully charge.
- Then, power on the nodes.
⚠️ Final Notes and Warnings
- This fix is a workaround for initial deployments only.
- Do not use this method in production environments without Dell EMC support.
- If the battery is physically faulty, it must be replaced.
By following the above procedure carefully, you can restore full functionality to your Dell Isilon cluster during the initial setup phase.