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      • Azure Policy based VPN
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  • Automation
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    • Python
      • Parsing mac address with regex
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  • Networking
    • OSPF states
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    • MST acronyms explained
    • Rapid Spanning Tree
  • Linux and Open-source
    • Wireshark and SNI
    • tcpdump – filter Path MTU messages
    • Linux route-based VPN + eBGP
    • NetBox API request
    • NetBox adding objects over API
    • Remote access VPN IKEv2
    • Check vendor with API
    • tcpdump – filter Path MTU messages
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tech blog

Networking, Cloud, SRE and Automation

Post Categories Linux and Open-source
Post dateDecember 1, 2025Post last updated dateUpdated December 1, 2025

Envoy 503 race condition

Post author
Avatar pawel pawel
Post read time1 min read
Introduction In complex architectures involving multiple chained proxies certain configurations can expose subtle race...
0
Post Categories Linux and Open-source Security
Post dateNovember 9, 2025Post last updated dateUpdated November 22, 2025

Send SNI with cURL

Post author
Avatar pawel pawel
Post read time13 sec read
Introduction We can send the SNI without changing our DNS or hosts file with...
0
Post Categories Azure Cloud VPN
Post dateNovember 7, 2021Post last updated dateUpdated November 7, 2021

Azure Vnet to Vnet peering

Post author
Avatar pawel pawel
Post read time22 sec read
Introduction Vnet peering is a great way of connecting two separate Vnets with a...
Post tagsazure, bgp, vpn0
Post Categories Uncategorized
Post dateNovember 6, 2021Post last updated dateUpdated November 6, 2021

Wireshark and SNI

Post author
Avatar pawel pawel
Post read time9 sec read
Sometimes it is needed to capture the SNI = server name indication. This information...
Post tagsssl, tcp, wireshark0
Post Categories R&S
Post dateOctober 22, 2021Post last updated dateUpdated October 22, 2021

OSPF states

Post author
Avatar pawel pawel
Post read time25 sec read
OSPF states, so I won’t never forget them 😉 DOWN No hellos have yet...
Post tagsccie, ospf, routing0
Post Categories Automation Azure Cloud R&S Security VPN
Post dateSeptember 30, 2021Post last updated dateUpdated November 2, 2021

Azure Policy based VPN

Post author
Avatar pawel pawel
Post read time1 min read
By default, Azure uses route based VPN if we select IKEv2 option (either we...
Post tagsazure, cloud, routing, vpn0
Post Categories Automation Linux and Open-source Python R&S
Post dateSeptember 30, 2021Post last updated dateUpdated November 2, 2021

Parsing mac address with regex

Post author
Avatar pawel pawel
Post read time1 min read
Vendors use different mac address format. When capturing mac address or arp table, output...
Post tagsautomation, linux, python0
Post Categories Automation Cloud Linux and Open-source
Post dateAugust 13, 2021Post last updated dateUpdated August 13, 2021

NetBox adding objects over API

Post author
Avatar pawel pawel
Post read time1 min read
Introduction API of netbox allows to add new devices, prefixes, sites etc. programmatically. We...
Post tagsapi, netbox0
Post Categories Automation Cloud Linux and Open-source
Post dateAugust 12, 2021Post last updated dateUpdated August 12, 2021

NetBox API request

Post author
Avatar pawel pawel
Post read time58 sec read
Introduction The beauty of netbox is that we can pull any data we want...
Post tagslinux, netbox0
Post Categories Azure Linux and Open-source VPN
Post dateJuly 29, 2021Post last updated dateUpdated July 29, 2021

tcpdump – filter Path MTU messages

Post author
Avatar pawel pawel
Post read time9 sec read
When troubleshooting connectivity issues (e.g. clients are behind some sort of VPN tunnel) we...
Post tagsmtu, tcpdump0

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Recent Posts

  • Envoy 503 race condition
  • Send SNI with cURL
  • Azure Vnet to Vnet peering
  • Wireshark and SNI
  • OSPF states

Recent Comments

    Recent Posts

    • Envoy 503 race condition
    • Send SNI with cURL
    • Azure Vnet to Vnet peering
    • Wireshark and SNI
    • OSPF states

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