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Category Archives for "Networking"

Using fail2ban on Fedora

The fail2ban tool in Linux monitors system logs for signs of attacks, putting offending systems into what is called "jail", and modifying firewall settings. It shows what systems are in jail at any given time, and requires root access to configure and view findings. It's generally used on Linux servers.fail2ban primarily focuses on SSH attacks, but can be configured to look for other kinds of attacks as well.How to install fail2ban on Fedora 34 To prepare for installing fail2ban, it's a good idea to update the system first:$ sudo dnf update && sudo dnf upgrade -y Then install fail2ban and verify its presence on your system with commands like these:To read this article in full, please click here

NaaS adoption will thrive despite migration challenges

Network-as-a-service (NaaS) is gaining momentum, providing a subscription-based model that eliminates the need for enterprises to own, build, and maintain their own network infrastructure. By replacing conventional hardware-centric VPNs, firewall appliances, load balancers, and MPLS connections, NaaS technology promises adopters the ability to rapidly scale up and down in lockstep with demand while eliminating hardware costs and bolstering network security and service levels.To read this article in full, please click here

Automating NSX-T Deployments

Nicholas Michel open-sourced an automation solution (video) that deploys the whole NSX-T infrastructure stack including:

  • NSX-T manager virtual machines
  • NSX-T uplink profiles and IP pools
  • Transport zones and transport nodes (NSX-T modules on ESXi hypervisors)
  • Edge clusters including BGP, EVPN and BFD

Once the infrastructure is set up, his solution uses a Terraform configuration file to deploy multiple tenants: external VLANs, tier-0 gateways, BGP neighbors, tier-1 gateways, and application segments.

While the infrastructure part of his solution might be fully reusable, the tenant deployments definitely aren’t, but they provide a great starting point if you decide to build a fully automated provisioning system.

Tools 9. Monitoring Availability of Customers via HTTP GET, ICMP, and DNS via Dockerised Prometheus

Hello my friend,

in the previous blogpost we’ve started the discussion how you can improve your customers’ experience in your network via better observability of the network health with Prometheus by means of periodic automated speedtest and iperf3 measurements. Albeit it is very important and useful, it doesn’t tell you if the customers’ or your own resources are available. By resource we mean any exposed service, such as web page, streaming service, etc. Today you will learn how to setup a monitoring with Docekrised Prometheus to make sure that you know for sure if the services are available for customers.


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Why to Automate Monitoring?

Monitoring allows to make you aware, what is the state of resources you are interested in. At a bare minimum, you shall be notified if the state of resources deviates from the acceptable value and, therefore, crosses some threshold. At the same time, this is just the first step. The end goal Continue reading

Unlocking QUIC’s proxying potential with MASQUE

Unlocking QUIC’s proxying potential with MASQUE
Unlocking QUIC’s proxying potential with MASQUE

In the last post, we discussed how HTTP CONNECT can be used to proxy TCP-based applications, including DNS-over-HTTPS and generic HTTPS traffic, between a client and target server. This provides significant benefits for those applications, but it doesn’t lend itself to non-TCP applications. And if you’re wondering whether or not we care about these, the answer is an affirmative yes!

For instance, HTTP/3 is based on QUIC, which runs on top of UDP. What if we wanted to speak HTTP/3 to a target server? That requires two things: (1) the means to encapsulate a UDP payload between client and proxy (which the proxy decapsulates and forward to the target in an actual UDP datagram), and (2) a way to instruct the proxy to open a UDP association to a target so that it knows where to forward the decapsulated payload. In this post, we’ll discuss answers to these two questions, starting with encapsulation.

Encapsulating datagrams

While TCP provides a reliable and ordered byte stream for applications to use, UDP instead provides unreliable messages called datagrams. Datagrams sent or received on a connection are loosely associated, each one is independent from a transport perspective. Applications that are built on top of Continue reading

BGP communities for traffic steering – part 2: State Management across Data Centers

This post has been a while in the making and follows up on an article about BGP communities that can be found here. Then we followed it up with some more discussion about FW design and place, or lack there of, on this podcast which inspired me to finish up “part 2”.

Anyone who has ever had to run active/active data centers and has come across this problem of how do I manage state?

You can ignore it and prepare yourself for a late night at the worst time.

Take everyone’s word that systems will never have to talk to the a system in a different security zone in the remote DC

Utilize communities and BGP policy to manage state; which we’ll focus on here

One of the biggest reasons we see for stretching a virtual routing and forwarding (vrf) is to move DC to DC flows of the same security zone below FWs. This reduces the load on the firewall and makes for easier rule management. However, it does introduce a state problem.

We’ll be using the smallest EVPN-multisite deployment you’ve ever seen with Nexus 9000v and Fortinet FWs.

Inter vrf intra data center

The first flow we’ll look Continue reading

A Primer on Proxies

A Primer on Proxies
A Primer on Proxies

Traffic proxying, the act of encapsulating one flow of data inside another, is a valuable privacy tool for establishing boundaries on the Internet. Encapsulation has an overhead, Cloudflare and our Internet peers strive to avoid turning it into a performance cost. MASQUE is the latest collaboration effort to design efficient proxy protocols based on IETF standards. We're already running these at scale in production; see our recent blog post about Cloudflare's role in iCloud Private Relay for an example.

In this blog post series, we’ll dive into proxy protocols.

To begin, let’s start with a simple question: what is proxying? In this case, we are focused on forward proxying — a client establishes an end-to-end tunnel to a target server via a proxy server. This contrasts with the Cloudflare CDN, which operates as a reverse proxy that terminates client connections and then takes responsibility for actions such as caching, security including WAF, load balancing, etc. With forward proxying, the details about the tunnel, such as how it is established and used, whether or not it provides confidentiality via authenticated encryption, and so on, vary by proxy protocol. Before going into specifics, let’s start with one of the most common tunnels Continue reading

Heavy Networking 622: Intel’s Smart Edge Brings The Cloud To The Edge (Sponsored)

In today’s sponsored Heavy Networking show with Intel, we dive into recent Intel silicon announcements that are impacting how networking services will be delivered in the years to come. The edge of the network is set to change thanks to modern CPUs that accelerate network functions including packet processing and security. Joining us is Intel's Jeni Panhorst, Vice President & General Manager, Network & Edge Platforms Division to talk about recent Intel announcements at Mobile World Congress and what it means for networking at the edge.

The post Heavy Networking 622: Intel’s Smart Edge Brings The Cloud To The Edge (Sponsored) appeared first on Packet Pushers.

Heavy Networking 622: Intel’s Smart Edge Brings The Cloud To The Edge (Sponsored)

In today’s sponsored Heavy Networking show with Intel, we dive into recent Intel silicon announcements that are impacting how networking services will be delivered in the years to come. The edge of the network is set to change thanks to modern CPUs that accelerate network functions including packet processing and security. Joining us is Intel's Jeni Panhorst, Vice President & General Manager, Network & Edge Platforms Division to talk about recent Intel announcements at Mobile World Congress and what it means for networking at the edge.

Securing Cloudflare Using Cloudflare

Securing Cloudflare Using Cloudflare
Securing Cloudflare Using Cloudflare

When a new security threat arises — a publicly exploited vulnerability (like log4j) or the shift from corporate-controlled environments to remote work or a potential threat actor — it is the Security team’s job to respond to protect Cloudflare’s network, customers, and employees. And as security threats evolve, so should our defense system. Cloudflare is committed to bolstering our security posture with best-in-class solutions — which is why we often turn to our own products as any other Cloudflare customer would.

We’ve written about using Cloudflare Access to replace our VPN, Purpose Justification to create granular access controls, and Magic + Gateway to prevent lateral movement from in-house. We experience the same security needs, wants, and concerns as security teams at enterprises worldwide, so we rely on the same solutions as the Fortune 500 companies that trust Cloudflare for improved security, performance, and speed. Using our own products is embedded in our team’s culture.

Security Challenges, Cloudflare Solutions

We’ve built the muscle to think Cloudflare-first when we encounter a security threat. In fact, many security problems we encounter have a Cloudflare solution.

  • Problem: Remote work creates a security blind spot of remote devices and networks.
  • Solution: Continue reading

Domain Scoped Roles – Early Access

Domain Scoped Roles - Early Access
Domain Scoped Roles - Early Access

Today, Cloudflare is making it easier for enterprise account owners to manage their team’s access to Cloudflare by allowing user access to be scoped to sets of domains. Ensuring users have exactly the access they need and no more is critical, and Domain Scoped Roles provide a significant step forward. Additionally, with the introduction of Domain Groups, account owners can grant users access to domains by group instead of individually. Domains can be added or removed from these groups to automatically update the access of those who have access to the group. This reduces toil in managing user access.

One of the most common uses we have seen for Domain Scoped Roles is to limit access to production domains to a small set of team members, while still allowing development and pre-production domains to be open to the rest of the team. That way, someone can’t make changes to a production domain unless they are given access.

How to use Domain Scoped Roles

If you are an enterprise customer please talk with your CSM to get you and your team enrolled. Note that you must have Super Administrator privileges to be able to modify account memberships.

Once the beta has Continue reading

Cloudflare Observability

Cloudflare Observability
Cloudflare Observability

Whether you’re a software engineer deploying a new feature, network engineer updating routes, or a security engineer configuring a new firewall rule: You need visibility to know if your system is behaving as intended — and if it’s not, to know how to fix it.

Cloudflare is committed to helping our customers get visibility into the services they have protected behind Cloudflare. Being a single pane of glass for all network activity has always been one of Cloudflare’s goals. Today, we’re outlining the future vision for Cloudflare observability.

What is observability?

Observability means gaining visibility into the internal state of a system. It’s used to give users the tools to figure out what’s happening, where it’s happening, and why.

At Cloudflare, we believe that observability has three core components: monitoring, analytics, and forensics. Monitoring measures the health of a system - it tells you when something is going wrong. Analytics give you the tools to visualize data to identify patterns and insights. Forensics helps you answer very specific questions about an event.

Observability becomes particularly important in the context of security to validate that any mitigating actions performed by our security products, such as Firewall or Bot Management, are not Continue reading

Using Cloudflare One to Secure IoT Devices

Using Cloudflare One to Secure IoT Devices
Using Cloudflare One to Secure IoT Devices

There is probably an insecure device with an exploitable vulnerability sitting in your house. And your office. And probably even your child’s school. Cameras, printers, speakers, access control readers, thermostats, even heart monitors... all of these devices are, or can be, Internet of Things (IoT) devices. These IoT devices are seamlessly integrated into our modern lives to improve efficiency and control of our environments — yet they are notoriously insecure. This is due to the constrained nature of device hardware and their limited computational capacity, which often lead to minimize access controls, hard-coded passwords, and an inability to patch remotely.

The reality of this threat can play out dramatically. Take, for example, the 2016 Mirai botnet attack, in which hackers exploited millions of IoT devices to become a large-scale botnet network capable of launching DDoS attacks that took down major portions of the Internet, including Twitter, the Guardian, and CNN. These types of attacks are hardly an infrequent occurrence. Cloudflare experienced this reality firsthand in March 2021, when one of our potential vendors for physical security cameras, Verkada, was compromised. The incident allowed a hacker to access Verkada's internal support tools to manage the cameras remotely, enabling them to Continue reading

Introduction To Relational Databases For Network Engineers

The growth of network automation and NetDevOps as a whole has created a shift in the networking industry. The tried-and-true CLI is shifting to the API and CSV inventories are moving to YAML/JSON structures for infrastructure as code. The tools and libraries used with our network operating systems are only growing. One technology that I […]

The post Introduction To Relational Databases For Network Engineers appeared first on Packet Pushers.

No Is A Complete Sentence

Has someone asked you to do something recently that you know you don’t have time to do but felt like you needed to do anyway? Or has someone tried to get you to help with something and impressed upon you just how important it is? You probably told them “yes” out of guilt or obligation or some other kind of negative emotion. Sure, you could have declined but you thought about how bad you would feel if someone did the same to you.

Let me tell you clearly. “No” is a complete sentence. It requires no explanation or defense. It is the only thing you need to say when you know you won’t be able to do something no matter how much the other party tries to get you to agree.

Everything Sucking Equally

If you know anything about QoS, you know that once a given circuit reaches the limitation for bandwidth you can no long send additional information. What’s counterintuitive about this is most people would assume that if you try to squeeze one more stream or packet into the mix that only that last packet would be affected and everything else would work perfectly fine, right? Only one Continue reading

Commitment to Customer Security

Commitment to Customer Security
Commitment to Customer Security

Cloudflare has been hooked on securing customers globally since its inception. Our services protect customer traffic and data as well as our own, and we are continuously improving and expanding those services to respond to the changing threat landscape of the Internet. Proving that commitment is a multi-faceted venture, the Security Team focuses on people, proof, and transparency to ensure every touchpoint with our products and company feels dependable.

People

The breadth of knowledge of the Security Team is wide and bleeding edge. Working as a security team at a security company means being highly technical, diverse, willing to test any and all products on ourselves, and sharing our knowledge with our local and global communities through industry groups and presenting at conferences worldwide. Connecting with our customers and counterparts through meetups and conferences lets us share problems, learn about upcoming industry trends, and share feedback to make improvements to the customer experience. In addition to running a formally documented, risk-based security program for Cloudflare, team members drive continuous improvement efforts across our Product and Infrastructure teams by reviewing and advising on changes, identifying and treating vulnerabilities, controlling authorization and access to systems and data, encrypting data in Continue reading

Zero Trust client sessions

Zero Trust client sessions
Zero Trust client sessions

Starting today, you can build Zero Trust rules that require periodic authentication to control network access. We’ve made this feature available for years for web-based applications, but we’re excited to bring this level of granular enforcement to TCP connections and UDP flows.

We’re excited to announce that Zero Trust client-based sessions are now generally available. During CIO Week in 2021, we announced the beta program for this feature. We incorporated feedback from early users into the generally available version. In this post, I will revisit why Zero Trust client-based sessions are important, how the feature works and what we learned during the beta.

Securing traffic with Sessions

We built Zero Trust client-based sessions to enhance the security of Cloudflare’s Zero Trust Network Access (ZTNA). The Zero Trust client is software that runs on a user machine and forwards all traffic from the machine to Cloudflare before it is sent over the Internet. This includes traffic bound for internal IPs and hostnames that typically house sensitive business applications. These sensitive applications were traditionally accessed using a VPN. Unlike VPNs, Cloudflare’s ZTNA allows administrators to set granular policies about who can access a specific resource. The only piece missing was that once Continue reading