We were using a DNS VS listening on port 53 but configured to handle TCP protocol as shown here: ltm virtual /Common/VS_DNS { destination /Common/10.10.10.10:53 ip-protocol tcp mask 255.255.255.255 pool /Common/pool_dns profiles { /Common/tcp { } } source 0.0.0.0/0 source-address-translation { pool /Common/SNAT-10.10.10.10 type snat … “F5 TMM Crash”
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The following script can be utilized to execute a ping sweep of a /24 network on Cisco Nexus switch. This has been tested and verified on Cisco Nexus 7K running 6.2.8a code version. Actual script: tclsh for {set i 1} {$i < 255} {incr i} … “Cisco Nexus – Ping Sweep”
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The following article is a brief introduction to IPSec VPN that is utilized to provide a logical connection between 2 sites (Site to Site) or a client and a site (Client to Site). The article is written to provide the key terms behind IPSec VPN … “IPSec VPN – Key Terms”
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F5 certification bridges the gap between Networking and Advanced Application Layer Stack. It takes about 8-12 months to develop a test. I was fortunate to be part of the Item Development Workshop (IDW) for F5 201v2 exam and wanted to share some of the information … “F5 Certification – Concepts”
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In this article, I am taking a shot at trying to explain the interaction between Delayed ACK and Nagle’s algorithm and how this could add latency during TCP session that requires transmission of small packets. MSS: Maximum Segment Size or MSS denotes the data that … “Delayed ACK and Nagle’s Algorithm”
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What ? Ansible is a simple IT automation tool. Ansible exists as CLI & GUI. GUI is called the Ansible Tower and Ansible, Inc., which is owned by RedHat, officially supports this. Controlling Nodes: The Network infrastructure is managed from Controlling Nodes. In an Enterprise environment, Controlling … “Ansible – The Why ?”
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Requirement: Client sends request to http://xyz.com/ Server needs to process http://xyz.com/append but client should only see http://xyz.com/ i.e., the URI /append should not be visible to the client. when HTTP_REQUEST { if { ([HTTP::host] equals “www.xyz.com”) and ([HTTP::uri] eq “/”) } { HTTP::uri “/append” } … “F5 iRule – URI Masking”
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For a project, I had to gather data in order to measure the SRX performance under different traffic loads. This was done for a SRX chassis system in cluster mode. The following commands were utilized in order to capture metrics when the system was subjected to … “SRX Performance Testing”
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The goal of this article is to explain configuration implementation on Cisco IOS after the config has been generated as shown in Ansible Config Generator III: config-implementation.yml — – hosts: switch gather_facts: true connection: local tasks: – name: OBTAIN LOGIN … “Ansible – Cisco Config Implementation”
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