The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

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Archive for the ‘Internet’ Category

Mikrotik – Choosing your SFP/SFP+ modules and direct access cables

Posted by jpluimers on 2017/05/09

For hooking up SFP and SFP+ ports on Mikrotik devices you basically have two options:

  • Direct Access Cable (passive and affordable for 1 and 2 meters; active and more expensive for more than 3 meters)
  • SFP/SFP+ modules with LC-LC optic fiber cable in between them (pairs of modules are more expensive than passive DAC, but the fiber is a lot cheaper)

Choosing the SFP/SFP+ modules is a bit intimidating as the MikroTik SFP module compatibility table – MikroTik Wiki has very few details.

Then I found sfp_all-150601132341.pdf (archived) which lists many of the SFP and SFP+ modules including their specifications.

Since neither the matrix nor the PDF contains links to the products, here is a small list of what I could source last year and is compatible with both the CCR1009 routeres and CRS226 switches:

–jeroen

via: Connect CCR1009 with CSR226 over a longer distance than 3 meter – MikroTik RouterOS

Posted in Internet, MikroTik, Power User, routers | Leave a Comment »

Some links for MikroTik tips and scripts

Posted by jpluimers on 2017/04/25

MikroTik has great hardware, but getting things to work can be a bit ehm intimidating.

So here are some links that were useful getting my CCR1009 and CRS226 configurations to do what I wanted.

Very advanced stuff:

Packet flow (maybe the toughest part to wrap your head around):

Scripts:

Load balancing:

Syntax highlighting:

Pictures

Very well written blog:

Manito Network’s Mikrotik solutions blog. In-depth articles on Mikrotik routing, security, best practices, VPN, and more.

Source: Mikrotik — Manito Networks

Solutions for RouterOS-based Mikrotik networks. Includes security and best practices, VPN, routing, switching, and more.

Source: Mikrotik-1 — Manito Networks

–jeroen

Posted in DNS, Internet, IPSec, MikroTik, Network-and-equipment, OpenVPN, Power User, PPTP, routers, VPN | Leave a Comment »

Powering Raspberry Pi devices from a Fritz!Box USB connection

Posted by jpluimers on 2017/03/30

I tried to power both Raspberry B+ and Raspberry 2 B devices via the USB ports of both a Fritz!Box 7490 and Fritz!Box 7360.

At first this works, but the Raspberry B+ devices over time would become unstable: not being able to ping and/or boot.

So below are some links on power requirements and powering Raspberry Pi A, B, A+, B+, 2B and zero.

Fazit/TL;DR: use an external power supply when available.

Read the rest of this entry »

Posted in *nix, Development, Fritz!, Fritz!Box, Hardware Development, Internet, Linux, openSuSE, Power User, Raspberry Pi, SuSE Linux | Leave a Comment »

Sniffers, Packet Capture – PFSenseDocs – cool, as it uses tcpdump/Wireshark format!

Posted by jpluimers on 2017/03/13

I hadn’t done a lot with pfSense in the past, which I regret a bit since I discovered this really cool feature: Sniffers, Packet Capture – PFSenseDocs.

The coolness isn’t so much that you can capture packets, but that it’s compatible with tcpdump and Wireshark (which has become available natively for Mac like 2 years ago).

Which means that you can download captures and open them in Wireshark.

So it’s as easy as 1,2,3:

  1. Set-up the capture on your router https://a.b.c.d/diag_packet_capture.php and start it
  2. Stop the capture and download the file
  3. Open the file in Wireshark or convert it to text using tshark

–jeroen

Posted in *nix, *nix-tools, Internet, Monitoring, pfSense, Power User, routers, tcpdump, Wireshark | Leave a Comment »

Getting the IP addresses of gmail MX servers – via Super User – dig isn’t enough

Posted by jpluimers on 2017/03/06

I needed the current IP-addresses of the gmail MX server (don’t ask the details; but it has to do with the brain-dead TP-LINK ER5120 configuration possibilities).

This is the command I finally used:

dig @8.8.8.8 +short MX gmail.com | sed "s/^[0-9]* //g" | sed "s/.$//" | xargs -I {} dig @8.8.8.8 +short {} | uniq | sort

Basically it’s a three stage sequence which had to work on OS X as well as Linux using a bash shell:

  1. Use the Google DNS servers (either 8.8.8.8 or 8.8.4.4)
  2. Get the FQDNs of MX records of gmail.com which are the mail servers for GMail.
  3. Translate these in IPv4 addresses
  4. Filter into a distinct list (just in case entries are duplicate: they aren’t yet, but might be)

The basics of the above are about using dig to get short (or terse) answers with as little (but still to the point) information as possible.
Read the rest of this entry »

Posted in *nix, *nix-tools, DNS, Power User | 1 Comment »

Trojans communicating through DNS: Cisco’s Talos Intelligence Group Blog: Covert Channels and Poor Decisions: The Tale of DNSMessenger

Posted by jpluimers on 2017/03/06

DNS traffic within corporate networks should also be considered a channel that an attacker can use to implement a fully functional, bidirectional C2 infrastructure.

Source: [WayBackCisco’s Talos Intelligence Group Blog: Covert Channels and Poor Decisions: The Tale of DNSMessenger

–jeroen

Posted in DNS, Internet, Power User, Security | Leave a Comment »

Multiple wifi access points / seamless handoff – Spiceworks

Posted by jpluimers on 2017/01/27

These seem to be the brands to look into:

  • Ubiquiti
  • Meraki
  • Ruckus

Source: Multiple wifi access points / seamless handoff – Spiceworks

–jeroen

Posted in Internet, Power User, Ubiquiti, WiFi | Leave a Comment »

Convert FRITZ!Box 7360 to Managed Switch (or even Access Point) having it’s own IP address: Setting up the FRITZ!Box as an IP client – via AVM International

Posted by jpluimers on 2017/01/23

This was a tad difficult to find as I searched for “Convert Fritz!Box to Switch” instead of “Convert Fritz!Box to Access Point”.

Since I had an old Fritz!Box 7360 lying around (from my ADSL era) and wanted to extend the cabled LAN for my brothers Fritz!Box 7490 with some low-bandwidth devices (max 100 megabit/second) I searched for Switch. My bad.

Oh I had to factory reset it as well as I forgot the management credentials. The AVM help on this is cumbersome: Loading the FRITZ!Box factory settings | FRITZ!Box 7360 | AVM International but the xs4all help includes a web-reset procedure as part of Internet: Reset procedures van mijn FRITZ!Box 7360 which translates to:

  1. Switch off the Fritz!Box (as this procedure needs to be done within 10 minutes of switching it on)
  2. Connect LAN2 to your computer
  3. Switch on the Fritz!Box
  4. Wait for a DHCP IP or (if you know the IP addresses) configure IP manually
  5. Go to the web-interface URL
  6. Indicate you forgot your password:

    Forgot your password?

    Forgot your password?

  7. Indicate you want a factory reset:

    Restore Factory Settings

    Restore Factory Settings

Anyway: with the above steps it becomes a Managed Switch (and if you don’t disable WiFi: Access Point too) that uses the primary internet connection as DHCP server (so it gets an IP address itself as well which means you can manage it).

Read the rest of this entry »

Posted in ADSL, Fritz!, Fritz!Box, Internet, Power User | Leave a Comment »

linux port forwarding to external ip – Google Search

Posted by jpluimers on 2017/01/20

For my Link Archive via linux port forwarding to external ip – Google Search:

Need to look at this more closely, but it looks like you need PREROUTING, FORWARD and POSTROUTING and two NATs (DNAT and SNAT), as this graph from Port Forwarding Using iptables – SysTutorials shows:

PACKET IN
    |
PREROUTING--[routing]-->--FORWARD-->--POSTROUTING-->--OUT
 - nat (dst)   |           - filter      - nat (src)
               |                            |
               |                            |
              INPUT                       OUTPUT
              - filter                    - nat (dst)
               |                          - filter
               |                            |
               `----->-----[app]----->------'

–jeroen

Posted in *nix, *nix-tools, Internet, Internet protocol suite, iptables, Linux, openSuSE, Power User, routers, SuSE Linux, TCP | Leave a Comment »

In this tutorial you will learn how to configure pfSense to load balance and…

Posted by jpluimers on 2017/01/13

In this tutorial you will learn how to configure pfSense to load balance and fail over traffic from a LAN to multiple Internet connections (WANs) i.e.… – Joe C. Hecht – Google+

Source: In this tutorial you will learn how to configure pfSense to load balance and…

Posted in Internet, pfSense, Power User, routers | Leave a Comment »