포항 개발자 아재의 실무 노트

Server

CLI로 서버 문제를 빠르게 진단

바로가기 →

$ ssh kosuni@server
Welcome to Ubuntu 22.04 LTS (GNU/Linux 6.x)

$ sudo tail -n 50 /var/log/nginx/error.log
2026/01/29 10:12:41 [error] upstream timed out while reading response header ...
2026/01/29 10:12:42 [warn] client sent too large body: 15728640 bytes ...

$ sudo nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

$ sudo systemctl restart php7.4-fpm
$ curl -I https://example.com
HTTP/2 200

PHP

실무에서 자주 터지는 문제, 짧게 해결

바로가기 →

<?php
declare(strict_types=1);

require __DIR__ . '/api/_db.php';
require __DIR__ . '/api/_auth.php';

function h(string $s): string {
  return htmlspecialchars($s, ENT_QUOTES, 'UTF-8');
}

$id = (int)($_GET['id'] ?? 0);
if ($id <= 0) {
  http_response_code(404);
  echo '<script>alert("This page does not exist.");location.href="/";</script>';
  exit;
}

$stmt = $pdo->prepare("SELECT * FROM posts WHERE id=:id LIMIT 1");
$stmt->execute([':id' => $id]);
$post = $stmt->fetch(PDO::FETCH_ASSOC) ?: null;

?>

Database

느린 쿼리/인덱스/백업까지 실전 노트

바로가기 →

-- slow query quick check
EXPLAIN SELECT id, title, published_at
FROM posts
WHERE status = 1 AND board = 'server'
ORDER BY published_at DESC
LIMIT 20;

-- index tune
ALTER TABLE posts
  ADD INDEX idx_board_status_published (board, status, published_at);

-- backup
mysqldump -u root -p kosuni posts boards > backup_2026-01-29.sql