Knowledge

• Modify Service Console IP Settings
  The Service Console (SC) is a essential part of an ESX host to manage the system. When installing the ESX host you need to configure a SC with IP addresses, and later on you can add additional SCs, change a SC or delete an SC. A Service Console usually is a port group within a vSwitch. This same vSwitch can be used for other networking issues as well, but best is to limit the amount of traffic that this vSwitch has to handle, for example no IP storage traffic if possible.
  • To add a Service Console Interface
  • To change the IP settings of an existing Service Console

    You can change the addres and subnet of an existing service console. Remember that when doing so you network connection will be terminated! Best is to do so from the console.
    For ESX you can type the command:

    

    esxcfg-vswif vswif0 -i 192.168.1.2 -n 255.255.255.0

    For ESXi you best use the GUI:
    • Select a ESX host
    • Select the tab “Configuration”
    • Select “networking” under hardware
    • Click “Properties” next to an existing vSwitch
    • Select your VMotion Port Group and click “Edit”
      
    • Select “Continue modifying this connection…”
    • Select the tab “IP Settings”
      
    • Change the IP settings to you needs. Remember network connectivity will probably be lost.
• Configure Service Console availability
  Service Console Availability can be configured in two way’s:
  • You can assign multiple NIC’s to the vSwitch where the Service Console is running on. When wired adequately to different switches this will provide a level of high availability to you Service Console. It will protect you agains NIC, wire and switch failure.
  • The Second option is to create a second Service Console, preferable on virtual and physical different network segments. This option has some more configuration as for the second SC a gateway has to be configured via the advanced network settings. There are many good walkthroughs out there who can help you to configure this. Read more here. http://communities.vmware.com/thread/227140 This will protect you againt all the failures a second NIC will, and also helps to combat configuration issues you might have on the service console / service console IP settings.
• Configure DNS and Routing settings for an ESX Host
To make you Service Console work adequately and reachable setting up you IP settings, including DNS resolvers and IP gateway, is essential. The DNS will be used for resolving hostname, and Is required for a decent operation of techniques as HA and DRS. A correct IP routing / IP gateway is needed for you SC to be reachable from other IP subnets. 

Both those settings can be configured from the GUI and the CLI.
  • DNS – GUI
To configure DNS settings via the GUI:
    • Select a ESX host
    • Select the tab “Configuration”
    • Select “DNS and Routing” under “Software”
    • Select “Properties” in the upper right corner
      
    • Adjust the DNS servers and domain name(s) to your needs.
  • DNS – Command line
To change the DNS settings from the commandline:
Edit the file /etc/resolv.conf
    • This file holds the DNS servers for name resolution and the local domain name. Example:

      

      nameserver 192.168.1.1
      nameserver 195.241.77.55

      search b3rg.local

    • More info and advance settings can be found here under “Configure Hostname Resolution”.
      
  • Routing – GUI
    To configure DNS settings via the GUI:
    • Select a ESX host
    • Select the tab “Configuration”
    • Select “DNS and Routing” under “Software”
    • Select “Properties” in the upper right corner
    • Select the tab “Routing”
      
    • The SC default gateway is used for your service console, the VMkernel default gateway is used for you storage IP settings. Adjust to your needs.
  • Routing – CLI
    VMware allows a default gateway for iSCSI, VMkernel and VMotion (when separated on different networks) but does not require one.  You can set the VMkernel default gateway / gateway of last resort with the command:
    

    esxcfg-route <DefaultGatewayIP>

    You can add additional or specific routes with the following command:
    

    esxcfg-route -a default <Subnet> <GatewayIP>

    
    During some surfing on the web I found this forum posting on the VMware website. Apparently it is not possible to have a separate gateway for you Service Console and for IP based storage on ESXi (ESX should work). This means that if you would like to use IP based storage on ESXi you need an interface in the same subnet as you SC is. Read more here.
    

Tools

• ESX/ESXi Configuration Guides
• Product Documentation
• VMware vSphere Client