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VMware Cloud Director 10.6.1 is the latest release of VMware Cloud Director. It includes a number of new features and enhancements, as well as some known issues and workarounds. Sure, here is a blog post based on the VMware Cloud Director 10.6.1 Release Notes: VMware Cloud Director 10.6.1 […]
Learn about the best homelab networking ecosystem options including Unifi, Mikrotik, Omada, Engenius, and Meraki Go
A list of compatible mini PCs with 128 GB RAM. Mini PCs that I have tested or know that others have tested with Crucial 128 GB of RAM
I had a customer that recently reached out asking how they could easily audit their entire ESXi infrastructure to determine which hosts was still booting using the legacy BIOS firmware, which has been deprecated and will be removed in a future vSphere release, in favor of the industry standard […]
This is session #2 of our Study Group. Covered areas are listed below:
If you have been following my recent adventures in playing with both Authentik and Keycloak as an OAuth/OIDC Identity Provider (IdP) for use with vCenter Server or VMware Cloud Foundation (VCF) Identity Federation, you can take it one step further and authenticate with a Yubico YubiKey or Apple […]
Ready to tackle the VCP – #VCF exam?Ready to tackle the VCP – #VCF exam?Join our #vmwarecode community-led study groups for support! These groups are meeting weekly at 9 AM EST to break down core concepts from the official exam guide. It’s a collaborative, open space—no rigid lessons, just community-driven discussions, resources, and insights.
When troubleshooting ESXi network and Syslog server connectivity issues, knowing the right tools can save you hours of frustration. Whether it’s an unresponsive syslog server, blocked TCP/UDP ports, this guide will help you diagnose and fix common connectivity issues quickly.
Key Troubleshooting Tools for ESXi Network Connectivity
Before checking anything else, confirm that the ESXi host can communicate with the syslog server at a basic network level.
Standard ICMP ping test:
ping <destination-IP>
VMkernel-specific ping (useful for vMotion, NFS, etc.):
vmkping <destination-IP>or specify which vmkernel should be used as ongoing interface for ping
vmkping -I vmk0 <destination-IP>
If these fail, the issue is likely a network routing problem or an upstream firewall blocking traffic.
Even if the server is reachable, the syslog port might be blocked or not listening. Netcat helps determine if a specific TCP or UDP port is reachable.
Note: Be aware that netcat doesn’t display an error message when a connection fails—only a successful connection is reported.
Use Cases
Test TCP Port Connectivity:
nc -z <destination-ip> <destination-port>Test UDP Port Connectivity:
nc -zu <destination-ip> <destination-port>
ESXi provides tools to inspect active network connections and adapter performance.
Check active TCP/UDP connections:
esxcli network ip connection list|grep <port>
If the syslog connection isn’t listed, ESXi isn’t attempting to send logs—double-check your syslog configuration in vSphere.
Check NIC statistics for errors and dropped packets:
esxcli network nic stats get -n <vmnicX>
Persistent errors here could indicate network congestion or misconfigurations.
Troubleshooting network issues between an ESXi host and a syslog server doesn’t have to be a headache. Using these tools, you can pinpoint the problem—whether it’s a blocked port, misconfiguration, or network adapter issue—and resolve it efficiently.
Still facing issues? Look at Broadcom KB
The introduction of VPCs (Virtual Private Cloud) at the network level provides a “self-service” for network, security and other network services in an isolated environment. Those responsible for the VPC can create networks and security rules (within their limits), thus relieving the burden […]
