In the our last couple articles a while ago, we discussed how anyone can use SSH to safely transfer files between Linux servers or how to use SSH to create tunnels between your local PC and a remote server. They're great tools and can be extremely useful, but it does require you to configure proper tunnel first. It also has the glaring limitation of being unable to access any resource outside of your server. So, with that in mind, let's talk about VPN and what it can do for us.
One of the the basic foundations of working with Linux is delegating file access permissions: who can access the file and who can manipulate it. Default file permissions for system files are usually already set by the OS. However new files created by users and third party programs need to be taken care of manually. Missteps in setting up file permissions can lead to problems with the system, newly installed programs, and potentially increase security risks. More importantly, this can lead to authentication and authorization errors.
SPF records detail which servers are allowed to send mail for your domain. You're supposed to be listing the addresses of all the servers that are authorised to send mail coming from your domain. If you don't have an exhaustive list at this time, it's generally not a good idea to set up an SPF record. Also a domain can only have one SPF record, so you'll need to combine all the information into a single record.
Both User Datagram Protocol and Transmission Control Protocol, UDP and TCP respectively, are transportation protocols working on the transport layer for the TCP/IP model. While you'll deal with both quite often, they're used for different purposes.
While your mileage may vary, most people hold critical data on their servers. If it's just a server for personal use, that's still time, resources, and effort invested in setting it up and keeping it running. Time that now has to be backtracked and spent again on reconfiguring everything.
If you're running the server for business or research, there will be a lot of people directly dependent on that server being up. Going down means losing money and losing trust, on top of the resource and time investment I already mentioned.
How ready are your servers for hardware failure? Electrical outage? Natural disaster? A good backup strategy will account and compensate for as many potential interruptions as possible.
There are multiple ways to set up 32-bit support on modern systems. Hit the link to check them out.
Getting through your buffers and cache is pretty straight forward and requires just a couple of scripts. Check this out.
Multithreading is becoming less of a standard and more of an abundance, with consumer level hardware reaching and exceeding 32 threads. So that brings the question: how many threads can your OS even handle? How does Linux handle all this firepower? As we find out in this article; ez.
Chances are that if you found this page through a Google search, you're probably looking for information on how addressing and routing actually works, without getting too deep into the complicated, underlying logic and binary math that serves as the foundationg for modern networking. At some point, I was looking for just this kind of information and ended up spending untold hours poring through texts trying to put it all together. So my goal with this article, is to save you as much time as possible. However, because it's so fundamental to routing, avoiding math entirely won't be possible.