Understanding Log Importance and Operations in Distributed Architecture

Logs are time‑ordered records of system events that help locate errors, analyze performance, and support security auditing.

In large‑scale distributed architectures logs become essential for troubleshooting, performance optimization, and business decision making.

Effective log operations require centralized collection, standardized formats, and tools that can ingest, store, query, and visualize log data.

The article discusses why operational tools are needed, outlines requirements such as risk analysis, alerting, and post‑incident review, and introduces common solutions like the ELK stack, Prometheus, and tracing systems (OpenTracing, SkyWalking).

It also presents a Go example for batch log retrieval via SSH, demonstrating how to execute remote commands concurrently.

Finally, it lists common log “bad smells” and good practices, emphasizing clear levels, consistent formatting, sufficient detail, and integration with metrics and tracing to achieve full observability.

package main

import (
    "fmt"
    "log"
    "os/exec"
    "runtime"
    "sync"
)

var wg sync.WaitGroup

func main() {
    runtime.GOMAXPROCS(runtime.NumCPU())
    instancesHost := getInstances()
    wg.Add(len(instancesHost))
    for _, host := range instancesHost {
        go sshCmd(host)
    }
    wg.Wait()
    fmt.Println("over!")
}

func sshCmd(host string) {
    defer wg.Done()
    logPath := "/xx/xx/xx/"
    logShell := "grep 'FATAL' xx.log.20230207"
    cmd := exec.Command("ssh", "PasswordAuthentication=no", "ConnectTimeout=1", host, "-l", "root", "cd", logPath, "&&", logShell)
    out, err := cmd.CombinedOutput()
    fmt.Printf("exec: %s
", cmd)
    if err != nil {
        fmt.Printf("combined out:
%s
", string(out))
        log.Fatalf("cmd.Run() failed with %s
", err)
    }
    fmt.Printf("combined out:
%s
", string(out))
}

func getInstances() []string {
    return []string{
        "x.x.x.x",
        "x.x.x.x",
        "x.x.x.x",
    }
}