# Troubleshoot Guide

## 1. Seeing "No Data" in Grafana

### Issue

Grafana panels show **"No Data"** even though the container/stack is
running.

### Reason

The **system date/time is incorrect** on the device. If the system time
is wrong, data timestamps fall outside Grafana's query window.

### Solution

Check the date/time using the command below:

``` sh
date
```

Set the correct date/time manually:

``` sh
sudo date -s 'YYYY-MM-DD HH:MM:SS'   # Replace with your actual date and time
```

Set date/time from the internet:

``` sh
sudo date -s "$(wget --method=HEAD -qSO- --max-redirect=0 google.com 2>&1 | sed -n 's/^ *Date: *//p')"
```

---

## 2. Influx -- Data Being Deleted Beyond Retention Policy (RP)

### Issue

- Data appears to be deleted beyond the configured retention policy
  (RP).
- InfluxDB 1.x deletes old data based on the retention policy duration
  and shard group duration.

### Reason

- Data is grouped into **shards**.
- Shards are deleted only when **all data inside them** is older than
  the RP.
- For RPs **≤ 2 days**, shard group duration = **1 hour**.
- InfluxDB always expires data at **RP + shard duration**.

Example:

For a **1-hour RP**: - Data written at **00:00** goes into the shard
covering **00:00--01:00**. - The shard closes at **01:00**. - InfluxDB
deletes the shard only when everything inside it is past the RP → at
**02:00**.

So the effective expiration time is **1 hour RP + 1 hour shard duration
= 2 hours**.

| Retention Policy | Shard Duration |Actual Expiry |
|---|---|---|
| 1 hour | 1 hour | 2 hours |
| 2 days | 1 hour | 2 days + 1 hr |
| 30 days | 24 hours | 30 days + 24 hr |

### Solution

- Understand that this is **normal and expected behavior** in InfluxDB 1.x.
- A 1-hour RP will **always** result in \~2 hours before deletion.
- No configuration can force deletion exactly at the RP limit.

---

## 3. Time Series Analytics Microservice (Docker) -- Takes Time to Start or Shows Python Packages Installing

### Issue

The Time Series Analytics Microservice takes time to start or displays
messages about Python packages being installed.

### Reason

UDF packages require several dependent packages to be installed during
runtime, as specified under `udfs/requirements.txt`. Once these
dependencies are installed, the **Time Series Analytics** microservice
initializes and starts inferencing.

### Solution

No action required --- wait for the **time-series-analytics**
microservice to complete downloading the dependent packages and
initialize Kapacitor to start inference.