Servers
How to Fix Permission Denied (publickey) on Ubuntu SSH
Read the client and server logs to find the real cause of a publickey refusal: the wrong key, the wrong account, or file permissions that OpenSSH rejects.
Hosting guides, tutorials and server insights
Practical articles on web hosting, WordPress, domains, servers and website security from the Siteharbour team.
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Servers
How to Install Docker on Ubuntu 24.04 Safely
Install Docker from its official repository, understand why published ports can bypass UFW, bind services to localhost, and prove the result with an external scan.
Servers
How to Fix 413 Request Entity Too Large on Nginx and PHP
Find which layer rejects a large upload, then raise the Nginx, Apache, PHP and application limits in the right order, and test with a real file.
Servers
How to Fix and Mitigate the PHP2Shell Vulnerability on Your Server
PHP2Shell (CVE-2026-109618 and CVE-2026-109619) can allow remote code execution. Find every PHP runtime, patch to the fixed versions, apply the mitigations, and check for compromise.
Email
How to Set Up Sendy With AWS SES on Ubuntu 24.04
Install Sendy on Ubuntu 24.04, verify your domain in Amazon SES, get out of the sandbox, handle bounces and complaints, and schedule campaigns with cron.
Email
How to Host Your Own Email Server
Decide whether to self-host mail, check the IP and reverse DNS first, then set up Postfix, Dovecot, SPF, DKIM and DMARC with the tests that prove mail is delivered.
Servers
How to Tune Nginx for a High-Traffic Website
Tune Nginx in the order that matters: measure first, raise the connection and file limits, reuse backend connections, cache repeat responses and limit abuse without blocking real visitors.
Web Hosting
When to Move WordPress from Shared Hosting to a VPS
Know when a shared WordPress plan is the real bottleneck, how to measure it, what an Nginx VPS changes, and a safe step-by-step move with the old site kept running.
Servers
How to Tune MariaDB for High Performance
Tune MariaDB on a dedicated server: measure first, size the InnoDB buffer pool, match I/O to NVMe, cap connections, keep durability safe and fix the slow queries with indexes.