Modern Fedora (29+) uses firewalld by default instead of the legacy iptables service. If you’re working with an older system or one configured for iptables, the concepts here still apply, but you should first check what’s actually managing your firewall: systemctl status firewalld systemctl status iptables If firewalld is active, use firewall-cmd instead. For iptables-based…
Package Installation Install the required packages: dnf install nfs-utils nfs-utils includes both server and client tools. The separate rpcbind package is no longer needed on modern systems — it’s handled as a dependency and runs as part of the NFS service. Configure /etc/exports Edit /etc/exports to define which directories clients can mount and with what…
Port forwarding allows external hosts to reach services inside a private network by mapping traffic from a public address to an internal one. On Linux, this is implemented through iptables rules that modify packet headers as they traverse the kernel’s netfilter framework. Common use cases include exposing HTTP/HTTPS servers from a private LAN to the…
Google Apps accounts can connect to Google Talk through XMPP, and Pidgin handles this well. Here’s how to configure it properly. Adding the Account Open Pidgin and create a new account. You’ll configure it across two tabs. Basic Tab Settings: Setting Value Protocol XMPP Username eric (local part of your email) Domain example.com (your domain…
A Linux box serving as a network gateway needs two network interfaces: eth0: Connected to the local network (LAN) with IP 192.168.0.1 eth1: Connected to the upstream network (Internet) with IP 198.51.100.1 The goal is to allow clients on the 192.168.0.0/16 network to route traffic through this gateway to reach external networks. Enable IP Forwarding…
A SOCKS5 proxy tunneled through SSH provides encrypted communication between your client and a remote server. This is useful for bypassing network restrictions, securing connections on untrusted networks, or routing traffic through a trusted server. Basic Setup The simplest approach uses SSH’s dynamic port forwarding with the -D flag: ssh -D 8080 username@sshd_server This creates…
When using lftp to connect to FTP servers, you may encounter a stall with “Making data connection” after logging in: < — 227 Entering Passive Mode (xx,xx,xx,xx,xx,xx) —- Connecting data socket to (yy,yy,yy,yy) port zz `ls’ at 0 [Making data connection…] The connection hangs indefinitely, though other clients like FileZilla work fine on the same…
Hadoop 1.x reached end-of-life in 2014 and is no longer maintained. This post documents a deprecated architecture for historical reference only. For new deployments, use Hadoop 3.x+ with YARN, which offers significant improvements in resource management, multi-tenancy, and reliability. See the Apache Hadoop documentation for current versions. For managed services, consider AWS EMR, Google Dataproc,…