Layer 2 loop troubleshoothing

Check that stupid interface statistics first if things are god damn wrong One network guy says I thought it is better to write the summary of the ports first. I have had multiple layer 2 loops in my career and they were mostly disastrous. I think there is nothing more scary than a layer 2
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PXE for network engineers

As a network engineer, you might receive a request from your colleagues probably Desktop team to configure network devices for PXE server. If you don’t know what PXE, how it works and configured, I will try to answer those questions on this post. Mostly I will focus on Windows imaging which I mostly configured devices
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Juniper SNMPv2 on routing instance

When I need to configure SNMPv2 on a Juniper device and routing instance is involved, I always forget to enable some knobs. Here is a quick one which allowed me to query an EX switch through its VR (in my example VR name is ISP1). You can also specify your specific VR name under “routing-instance-access”
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List trunk ports on Juniper Switch

Have you ever wanted to list the trunk ports on a Juniper EX switch? Unfortunately there doesn’t seem to exist a single dedicated command for this purpose. In the past I used to use the following command: > show ethernet-switching interfaces detail | match Trunk but this is not working on new releases. Juniper keeps
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SRX240 and SRX340 failure rates

Recently I upgraded dozens of SRX240H2 and SRX340 series Juniper firewalls and around %10 of SRX240H2 boxes either crashed during upgrade or after upgrade and none on 340 series. Although 340 is a newer platform, I would like to be positive and believe the fact that Juniper has improved both hardware and software quality. What
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SRX standard and structured syslogging

SRX can send the logs in two formats standard and structured. If you haven’t made any extra config, what you see in the traffic logs is usually standard one. However structured one is easier to read and parse. Look, it is in the format field_name = field_value, so you can parse it or more friendly.
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