Troubleshooting

The thumb-rule to troubleshooting of any product / solution / protocol is to find out more about your problem. Once you have identified the symptoms, finding a solution is not a difficult task. Majority of time the issues related to Infrastructure that is reported to VMware Technical Support has not been diagnosed properly. Due to that, …

STORAGE CONNECTIVITY TO VSPHERE

The VMware vSphere storage architecture consists of layers of abstraction that hide the differences and manage the complexity among physical storage subsystems. To the applications and guest operating systems inside each virtual machine, the storage subsystem appears as a virtual SCSI controller connected to one or more virtual SCSI disks. These controllers are the only types of …

VIEWING ACTIVE TCP/UDP CONNECTIONS WITH NETSTAT AND ESXCLI NETWORK

When troubleshooting network connectivity issues, it may be helpful to see all the active incoming and outgoing TCP/UDP connections on an ESX/ESXi host. ESX hosts can use the netstat command and ESXi 4.1 and later hosts can use esxcli network to show the list of TCP/UDP connections. The commands are: ESX 3.5/4.x – # netstat -tnp ESXi 4.1 – # esxcli …

CONFIRMING CONNECTIVITY TO A TCP PORT WITH TELNET

While the ping command confirms connectivity, it does not necessarily mean that all TCP ports on the remote host can be reached. It is possible for a network firewall to allow or block access to certain ports on a host.   To check if specific TCP ports are running on the remote host, you can use the telnet command …

HOST CRASH DIAGNOSTIC PARTITIONS

A diagnostic partition can be on the local disk where the ESXi software is installed. This is the default configuration for ESXi Installable. You can also use a diagnostic partition on a remote disk shared between multiple hosts. If you want to use a network diagnostic partition, you can install ESXi Dump Collector and configure …