24 February 2013

Jumbo frames in virtual FreeNAS 8.3.1 on ESXi 5.X

... and how to setup vmxnet3 vNIC and Jumbo frames


When I set jumbo frames (MTU=9000) on em0 vNIC in virtual FreeNAS I can't get frames bigger than 1500 between the peers, even configuring mtu=9000 in all network elements between end points. Do not be fooled if you see this:

[root@freenas] ~# ifconfig em0 mtu 9000
[root@freenas] ~# ifconfig em0 em0: flags=8843 metric 0 mtu 9000 options=9b
ether 00:50:56:87:xx:xx options=9b ether 00:50:56:87:xx:xx


I did some unsuccessful tests with em0 (in my case vnic is recognized as intel 82545EM) and MTU=9K. Eventually I could not get real jumbo frames between FreeNAS and other vm even inside vSphere host. Probably exception is being in the E1000 driver used by FreeNAS virtual machine though this also depends of physical NICs. em(4) supports variations of the hardware - some do jumbo frames, some don't. It could easily get a lot quirks in a VM, depending on how the VM emulates the card and the mode of networking used. This should show which of the Intel cards is being emulated.

# pciconf -lv | grep -A3 em0

Automated backup for Cisco UCS instances


1.    For each UCS cluster instance logon and create dedicated user with admin rights for backup purposes. 
2.    Enable HTTPS port on UCS cluster instance

 3.    Password for user “backup” out of Cisco UCS should be kept in secure string. It is already created and saved at file D:\UCS_SCRIPT\CISCO_UCS_BCKP_PWD.txt as secure string.

Note:     If there is a need for new password for new Cisco UCS instance different from currently used you have to create new text file for storing new secure string, otherwise you will overwrite
D:\UCS_SCRIPT\CISCO_UCS_BCKP_PWD.txt and logon will fail for all previously setup instances.

4.    Create new secure string from plain password.
   i.    Logon with local admin user to Windows box. Keep in mind this user should start scheduled job later so you have to setup it with same Windows credentials.
   ii.    Open Cisco UCS PowerTool or MS PowerShell.

Small scale markets

  Every business needs up to date information technology. Bulgarian companies also. They are pressured by increasing competition in business environment, but opening of Bulgaria to international markets, direct relation with the country’s entry into the European Union.
  Dealing successfully with challenges, they increasingly depend on the collaboration tools. Access to shared resources is the key. It may be common accessed information, applications and devices. They should rely on the reliability and accessibility at any time. This is the birth of naturally need a computer, which can store and process the most important information about the company – especially developed by the manufacturer system, called server.
  With the rapid and headlong development of industry – all high class servers with 4 and 8 processors technology are available for the lower class machines, designed for small and medium businesses. With attractive prices of course. However, companies limited by their own IT budgets are often hesitate – server or PC?

23 February 2013

VMware VM - changing the MAC address

The conversion of physical to virtual machine is related to change of the MAC address of the network interface. In some cases this can be a problem when software is installed where the licensing is bound up to the MAC address. To avoid the automatic change of MAC address, you should not move the machine (configuration file of VM) to another host or different datastores on the same host.
If the VM is a member in a DRS cluster and automatically or manually movement between different hosts is needed, then we must set up MAC to static and we can achieve this in few ways.

Method #1. vSphere Client

If your attempt failed with the error below - go to method 3
“The MAC address entered is not in the valid range. Valid values are between xx:xx:xx:xx:xx”

Method #2. MAC address change from within the network adapter settings in Windows.
First of all ensure that vSwitch (virtual port group) security settings MAC Address Changes and Forged Transmits are set to

21 February 2013

FreeNAS -8.3.0 UPS control via SNMP

UPS Service configurations to MGE Galaxy 5000 with WEB/SNMP Network Management Card Transverse 66074 - firmware version GG

This card acts as an SNMP agent and as a HTTP/Web server. It enables UPS supervision from the Network Monitoring System using SNMP and traps or simply from a web browser.
FreeNAS communicate with this card by NUT - Network UPS Tool. It would be helpful to read man page for NUT snmp-ups.

- Identifier - name of your UPS

- Driver - From the drop down menu choose the appropriate driver for snmp-ups:
MGE UPS SYSTEMS ups 5 Pulsar / Comet / Galaxy (SNMP) SNMP/Web Transverse card (ref 66074) (snmp-ups) 

Many of the choices listed are in fact the same driver as you can see below