Category Archives: Servers

Linux : Nginx error SSL_do_handshake() failed while SSL handshaking to upstream

Using Nginx as Apache reverse proxy and receiving “502 Bad Gateway” error and, additionally have something like this in your error log file? [error] SSL_do_handshake() failed (SSL: error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol) while SSL handshaking to upstream, client: 0.0.0.0, server: www.domain.tld, request: “GET / HTTP/1.1”, upstream: “https://127.0.0.1:4343/”, host: “www.domain.tld” Since you are using SSL, you obviously need… Read More »

Linux : Nginx error 413 Request Entity Too Large

Having this error while uploading large files with Nginx? 413 Request Entity Too Large or ; [error] client intended to send too large body 1. Edit the main Nginx configuration file : /etc/nginx/nginx.conf 2. Append the following and set the value to meet your needs (this example assume that the max upload file size is… Read More »

Linux : Ubuntu apt-get update Hash Sum mismatch

Experiencing the following error while running “apt-get update” on your Ubuntu server? W: Failed to fetch http://ca.archive.ubuntu.com/ubuntu/dist/precise/restricted/source/Sources Hash Sum mismatch E: Some indes files failed to download. They haev been ignored, or old ones used instead. Just run the following command : sudo rm -Rf /var/lib/apt/lists/* And run the update command again : sudo apt-get… Read More »

Linux : vsftpd refusing to run with writable root inside chroot

After updating vsFTPd (version 3.0.2 +), you may have noticed the following error while trying to log using a chrooted account : 500 OOPS: vsftpd: refusing to run with writable root inside chroot () This error would only happen if you have the following parameter enabled (chroot users into their home directory) : chroot_local_user=YES The… Read More »

How to disable SSL v3 for Microsoft IIS Server?

Due to the recent POODLE (Padding Oracle On Downgraded Legacy Encryption) SSLv3 vulnerability discovery, you may want to disable it to protect you and your visitors against this exploit. Here is the procedure for Windows Server/IIS. Note that older/obsolete browsers are not implementing TLS, shame on users for not doing their updates then! 1. Open… Read More »

Windows : Blocking IP from command line

Here is two commands to wither block a single or group of IPs on the Windows Firewall using the command line. Please note that you will need elevated privileges to run these commands. 1. Block a single IP (or subnet*) netsh advfirewall firewall add rule name=”IP Block” dir=in interface=any action=block remoteip=<IP_Address>/32 *You will need to… Read More »

Linux : Configuring SSL certificate with Nginx

Setting up SSL certificate with Nginx is quite easy, however slightly differ from the standard configuration since it require that the server certificate and the certificate authority (CA) to be bundled together within a single PEM file. NOTE : See this article if you are looking for the procedure how to generate a certificate key… Read More »

Linux : Bind loading master file domain.tld.hosts: ran out of space

Bind (named) DNS server is failing to reload or restart after modifying a domain TXT record? Have a look at your Bind log files (commonly written to /var/log/messages) and you may find the following entries : named: dns_rdata_fromtext: domain.tld.hosts:0: ran out of space named: zone domain.tld/IN: loading master file domain.tld.hosts: ran out of space named:… Read More »