• prosody xmpp server "Failed in all attempts to connect to proxy.eu.jabber.org"


    Aug 13 13:46:33 s2sout2d45040 info Failed in all attempts to connect to proxy.eu.jabber.org Aug 13 13:46:33 s2sout2d45040 info Sending error replies for 1 queued stanzas because of failed outgoing connection to proxy.eu.jabber.org No clue why it tries to use a proxy not explicitly specified. This could be because the proxy specified for the domain fails when someone is trying to se........
  • Postfix How To Change Sending IP Address To Specific IP Binding or Interface


    Ithought I'd post this becuase there is some bad information out there. Some guides tell you to edit /etc/postfix/master.cf (-o smtp_bind_address=) but this doesn't work. The same guide also says if you don't change it there you end up changing the listening IP/bind interface which is also not true. Here is a simple and effective way to change Postfix's sending/binding/outgoing IP address (very important for reverse DNS and so mail servers don't block you)........
  • Postfix how to secure outgoing authenticated e-mails for privacy and hide the IP address, mailer and other things


    The most common solution is to use the /etc/postfix/header_checks but this is a big problem. Why is header_checks a problem? Because it does it to all mail whether incoming or outgoing and whether authenticated or not. We of course want as much header information for incoming as we can get for many reasons but many organizations want to secure and make their mail clients as secure as possible. I adapted this solution to the client's custom config, they are configur........
  • Asterisk DOS attack - failed for '173.242.117.192' - Peer is not supposed to register [May 23 15:46:07] ERROR[32748]: chan_sip.c:13158 register_verify: Peer '153' is trying to register, but not configured as host=dynamic


    This happened to a customer Asterisk server and it somehow found the ID of the registration account to the upstream SIP server and was railing connection attempts (it filled up the console and there were literally thousands per second). Basically this caused all incoming and outgoing calls to fail. It was a temporary fix but the solution was to block that specific IP, it's hard to stop it 100% because the customer needs the default SIP port.........
  • List of Free Public DNS Servers IP Addresses


    One thing to note about DNS servers and providers is that they aren't always trustworthy, not even if they're Google or your favorite ISP. Any DNS server can compromise your privacy, and they are likely tracking your browsing habits and keeping logs of it. Sometimes it's for Marketing/Research purposes such as Google's GMail service which they admit is scraped/datamined. I would expect nothing less from their DNS service. The other danger with such widely used and pu........
  • email server messsages rejected without reverse DNS DNS check failure Client host rejected: cannot find your reverse hostname Cannot resolve PTR record


    Basically you should always be 100% sure that whatever IPyour mail server sends out with has reverse DNS/PTR records. Remember that unless you own your IPs then you won't be able to set your own reverse DNS. Even if you were to create a reverse PTR record on your DNS servers it will be ignored. Reverse DNS is queried to pre-assigned DNS servers of your ISP, so therefore you'll need to contact your ISP/Colo/Hosting provider to do a reverse DNS entry. If you don't have........
  • FUSE/Curlftpfs mount ftp account as drive partition in Linux


    This is a great way to use your ftp server space, for example on your web hosting account (althoughI believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect. Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc.. Name curlftpfs - mount a ftp host as a local directory Synopsis........
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