Month: December 2010

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Sr. UNIX Systems Engineer (Vinings, GA)

My company, Virima Technologies is seeking an experienced Senior Systems Engineer for opportunity with a client in Atlanta, GA.

DESCRIPTION:  Senior Unix Systems Engineer with experience working in datacenters and hosting facilities.  “Hands on” experience with Solaris and/or RedHat is required.

QUALIFICATIONS:
10+ years of UNIX systems experience in a large, 24×7 environment.
Must have experience in a highly-available UNIX environment.
Experience and deep knowledge of Solaris 9 and 10.
Experience and deep knowledge of RHEL 4.x and 5.x in a virtualized environment.
Sun Blade Center hardware experience required; other high end server experience a plus.
Advanced experience with Veritas Volume Manager (VVM) and Veritas Cluster Server (VCS) or equivalent.
Experience with BIND, Sendmail, and Apache servers.
Strong knowledge of infrastructure services: LDAP, DNS, NTP, NFS, and DHCP.
Knowledge of multi-tiered application architecture.
Strong experience and knowledge of OS system internals: memory management, scheduling, TCP/IP stack, etc…
Experience and knowledge with Ethernet, multicast, vlan tagging, RDMA, etc…
Ability to compile Linux kernels and driver modules.
Strong knowledge of RHEL Kickstart procedures.
Strong scripting skills: Korn, Perl, Bash, AWK, Sed. Python skills a plus.
Experience with networking (subnetting, routing, etc.)
Experience with SAN storage (provisioning, switching, fabrics)
Experience with ITIL practices.
Ability to document project designs, process, and policies.
RHCT and RHCE certification a plus.
Problem solving brings you great joy.

EDUCATION:
Bachelor’s degree or equivalent education in related fields.
Certificates of training in associated fields/equipment

Contact Doug Bramblett

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Configure your OS for Gigabit Ethernet

Get a new wireless router recently? If so, its a good bet that it has gigabit ethernet (GbE) capability that you can take advantage of.

Manufacturers have been slow to move away from the standard 10/100 network switches that were the mainstay of wireless routers for years.  However, today it is increasingly common to see routers with GbE switch ports.  Its also likely that your computer has a GbE network card built-in, if you bought it within the last five years.

Now that wireless routers have caught up, you need to setup your network card to enable GbE in your operating system.  Note: you can only use jumbo frames on a network if all devices, including the switch, support it. GbE also does not work over wireless connections.

The setting we will change is called “Jumbo Frames,” and enabling it will allow you to move packets around your wired home network much faster. Here is how you do it for the three major operating systems in use today:

1) Windows

Control Panel – Network and Sharing Center – Change Adapter Settings – Local Area Connection – Properties – Configure – Advanced tab – Jumbo Frame property

Set the value to the highest possible MTU value, which is usually a 9KB MTU, like this:

For a Mac, open System Preferences – Network – Ethernet – Advanced – Ethernet.  Select Configure: Manually and MTU:Custom settings.  This will bring up a textbox where you may enter in the 9000 value for jumbo frames:

For a Linux computer, edit the /etc/sysconfig/network-scripts/ifcfg-eth0 file and add a line called “MTU=5000” like this:

Once you enable these settings, reboot your computer to ensure they take effect. Once complete,  ping another computer on your network (presuming it also has GbE enabled) with “ping <ip address> -f -l 9000” to verify that jumbo frames are enabled. You should see a normal ping response (but with a larger buffer size thanks to jumbo frames):

You can now begin moving files around your network at gigabit ethernet speeds!