VMware Snapshots – Some Thoughts and Best Practice

VMware gives the capability to “snapshot” a powered on or powered off virtual machine, preserving its state at a particular point in time. Although this is a very useful feature, is it not intended as a long term backup, archive or for example a pre-upgrade/change state backup. A snapshot allows an administrator to create a […]

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Palo Alto Firewall – Command Line Example (Interface and Access Rules)

The Palo Alto Firewall GUI is really slick, but sometimes its handy to create using the CLI, perhaps if you have a large number of changes that need to be made at once. Within this example, we’ll create a zone, then an Interface (on an Aggregate Interface), give it an IP address, apply a management […]

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Microsoft Exchange 2016 Database not Mounting

We had an issue where a recent Windows update broke the Exchange Server, luckily booting into safe mode and removing it resolved the issue, however although the databases mounted okay, there was one that did not. We attempted the typical ESEUTIL steps because it was reporting “dirty shutdown”, and got the database back to a […]

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Multicast – IGMP Snooping and IGMP Querier – Sender and Reciever(s) in same VLAN/Layer 2 Segment

Multicast is a networking method used to efficiently transmit data to multiple recipients simultaneously. Unlike unicast (one-to-one) and broadcast (one-to-all) communication, multicast is a one-to-many or many-to-many method where data is sent only to devices that are interested in receiving it, rather than to all devices on a network. In multicast, devices that want to […]

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VMware PowerCLI Discover VMs Restarted by VMware HA (Host Failure)

VMware HA (High Availability) is a great feature, but if the failure occurs when you are not watching it you may well need to know what was affected. You can use VMware PowerCLI to query vCenter for the VMs that have been affected by a host failure causing an HA restart event. I’m assuming that […]

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AWS Transit Gateway with VPN to On-Premise Palo Alto Firewall

The AWS Transit Gateway can be used to join the networking of many VPCs (in the same or different AWS Accounts) within the same region together to facilitate communication, it may also be used in conjunction with DX (Direct Connect) or Site-to-Site VPNs to provide connectivity to other Cloud Platforms but additionally to on-premise networks […]

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VMware vCenter – “Exception in invoking authentication handler User password expired”

An appliance that was deployed over 90 days old with no changes made to the default settings. When attempting to logon to the VAMI console of the appliance i.e. https://vcenter.domain.com:5480 you get the message: “Exception in invoking authentication handler User password expired”. To resolve this you need to reset the password, then set it not […]

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