Installation and Set Up

1.How much rack space does a KVM switch require?
Depending on the size of the KVM configuration, for up to a 42-port solution, most KVM switches typically occupy 1U of rack space.Once you upgrade to a 64-port KVM solution, 2U of rack space will likely be required.

2.How difficult is it to install and set up KVM switches?
Most KVM switches are fairly easy to set up and feature "plug and play" functionality.The more cumbersome piece of this process is that each of the systems attached to the KVM switch may require a restart, depending on their peripheral connections.

4.What cabling options can be used with a KVM switch?
In smaller applications with ample cable space, coax 3-1 cables may fit the bill.Large installations will most likely require KVM switches that allow users to implement point-to-point UTP cabling.

6.What bandwidth is required for remote IP access?
Most compression technologies use differentials, sending only the changes that appear on a screen to update the user screen.However, your bandwidth requirements will vary significantly depending on the graphic intensity of the application you are using.

Expansion and Replacement

1.After installation, can I expand the solution?
Expanding the number of systems supported by a KVM installation is relatively easy.For example, the Raritan Paragon II 8-user, 32-port solution offer users an option to add 32 ports by adding the Raritan  P2-UMT832S stacking model to the main Paragon II 8x32 matrix switch with a 6-inch SCSI cable, so that it becomes an 8X64 architecture instead of an 8X58.

2.Can I easily add local user stations in a datacenter?
Yes.However, it is important to select a switch that will provide room to grow.If a KVM switch is not maximized at the user level, adding more users is as simple as connecting additional user stations with point-to-point UTP.Keep in mind that each analog KVM switch has a finite number of users; digital KVM switches allow more room for expansion.

3.What is the degree of difficulty in replacing switching equipment?
Replacing equipment is usually easy, as replacement dongles or KVM switches have "Plug-and-play" functionality.

Features of KVM Switches

1.Do KVM switches allow users to automatically cycle/scan video on all connected ports?
A "port scan" feature is often included with most, if not all, models of KVM switches.A simple hot-key command will permit users to view a selected list or all ports attached to the KVM switch and show the video of each for a selected amount of time.

2.What naming options do KVM switches offer?
KVM switches limit the amount of characters used to name servers through the OSD.Some OSD menu systems allow users to implement alpha and/or numeric naming conventions.

3.What is the resolution and performance over IP?
Resolutions vary by device, and some provide a maximum of up to 1600X1200 at 60Hz over IP.If you have high resolution requirements, consider analog KVM switches, as they provide a higher resolution than digital KVM switches.

Supported Features, Devices, and Platforms

1.Do KVM switches support serial devices (i.e., routers, headless Unix, etc.)?
Yes.Some high-end KVM enterprise solutions provide support for serial devices.Avocent and Raritan devices provide support for serial devices through the use of dongles, and Rose Electronics'devices provide serial support at the switch level and can support these devices through coax cables.

2.Can all types of devices (Sun, USB, AIX, SGI, RS6000, HP9000, DEC, MAC, chained IBM 330 servers, serial/TTY, etc) connect directly to a KVM switch?
Yes.Interface modules allow flexibility.All that is needed is the proper serial computer interface module or dongle with the right connections.Again, if a dongle is not available, an adapter such as a Raritan AUATC adapter, can be used to convert all serial connections to a standard PS2 keyboard and VGA monitor connection.

3.What client platforms does KVM over IP support?
Platform support varies by device.For example, Raritan offers a Java-based multi-platform client and will work with a wide variety of operating systems including Linux, Sun/Solaris, and Macintosh.Other devices use an Active-X platform and provide support only for Windows.

4.Can Sun users use their native Sun keyboard, mouse, and display?
Yes, some high-end products allow users to plug Sun peripherals into console ports.In addition, along with native Sun connections, users also have the choice between USB, and PS2 keyboard/mouse with VGA video.

5.Do KVM switches support audio?
Yes, some products provide audio support.For example, the Rose Electronics UltraView Pro series will support audio for users and computers.In addition, Avocent AMX devices provide multi-user switches that support audio functionality throughout.

Remote Power Management

2.Are 3-Phase and 208 power supported?
Yes.Enterprise-level solutions such as Server Technology's line of remote power management products, provide multiple options for 3-phase or 208 power.

Server Dongles

1.Is there a KVM switch that has the ability to split KVM signals from a single server and send them to two destinations?
Yes.Both the Raritan Paragon II and the Avocent AMX offers a dual-headed dongle for this purpose.This dongle permit users to have dual access into a single server from two separate matrix switching units.This type of dongle doubles the maximum user density for an installation.

3.Can dongles retain server name information?
Yes.No matter how long a dongle remains dormant, information will carry on when users move or upgrade computers.

Security and Access Rights

2.How user-friendly is the application to configure user and server rights and profiles?
On most devices, administrators simply point and click their way though the advanced OSD to create user profiles and assign access privileges for all users.The top enterprise offerings include a GUI software for this purpose.

3.Does a KVM's security features allow you to hide servers/devices from users who don't have sufficient access rights?
Yes.This feature is set through the "permissions and profiles" feature, and it is available on most enterprise-level Cat5 based, digital KVM switches, and analog KVM switches.

4.Does viewing multiple servers or devices create "blocking", which doesn't allow other users to work with those servers?
Blocking can be a problem when KVM switches are stacked or daisy-chained together. Daisy-chained switches leave users with a limited number of pathways to the upper-tier host computers.When all pathways are occupied, users will be blocked out of the remaining systems in the KVM architecture.

5.Do KVM manufacturers have realistic "non-blocked" remote access solutions for smaller remote sites?
Yes.Multiple manufacturers have 1X1 devices that allow for a non-blocked architecture.Depending on the size of this type of installation, you may want to aggregate these 1X1 devices through a centralized management appliance.

6.Do KVM switches offer a "Time Out" feature?
Advanced OSD features on many devices, including the Raritan Paragon II and the Avocent AMX series, for example, will allow administrators to set an automatic time-out feature to log out inactive users that are logged into the KVM system.

7.Can you back up the configuration/user rights database?
Back-up databases can be replicated for the Avocent DSR KVM over IP switch.The Hub and Spoke DSView 3 databases can be replicated up to 15 times for fail-safe redundancy.

결국 마지막 수단으로 BIOS 설정을 초기화 후 다시 설치하니 문제가 없었습니다.

특별히 변경한 항목은 없었는데 뭔가 문제를 일으킬만한 설정이 되어 있었나 본데요. 문제의 정확한 원인은 발견하지 못했지만, 위와 같은 증상을 해결할 수 있었습니다.

혹시 비슷한 경험으로 고민하시는 분들께 도움이 되었으면 합니다.

우리가 매일같이 사용하는 OS나 브라우저의 종류만 해도 아시다시피 적게는 몇 개에서 많게는 수십 여 가지가 있습니다.

종종 지구 반대편의 인터넷 사용자들은 과연 어떤 종류의 OS나 브라우저를 사용하고 있는지 궁금할 때가 있죠.

그래서 이런 도구들의 세계 시장 점유율을 한눈에 조회할 수 있는 사이트를 소개합니다.

*참고
해당 자료는 액티브 한 인터넷 사용자를 대상으로 브라우저를 통해 취득된 정보를 기반으로 작성되었으므로 정적, 폐쇄적 서버 환경에 운영되고 있는 시스템들에 대한 부분은 고려되지 않았음을 알려드립니다.

1. 운영체제 시장 점유율 - 플랫폼 별(2010.2월 기준)

아직까지는 윈도우XP의 점유율이 압도적이나 윈도우7의 강한 상승세에 힘입어 MS의 실패작(?)인 비스타와 함께 꾸준히 점유율이 낮아질 것을 예상해봅니다.

NT, 98, ME 등 윈도우 2000 이전 버전 OS 의 점유율이 모두 합쳐도 불과 1% 수준으로 추후 소프트웨어나 서비스 개발시 지원 여부를 신중히 검토할 필요가 있다는 생각이 듭니다.

웹 브라우저 시장에서는 지난 1년간 꽤나 많은 변화가 있었습니다. 그래프를 보시다시피 IE 8.0 과 파이어폭스 3.5 의 상승세로 간단히 요약될 수 있겠습니다.

우선 IE의 세대 교체가 급속히 진행되어 1년 전 1% 대에 불과하던 IE 8.0 의 점유율이 현재 22% 이상으로 급등하였으며, 이에 대한 반대급부로 30% 대를 유지하던 기존 IE 6, 7 버전은 1년만에 각각 10% 대로 내려앉으며 기존의 왕좌를 내어주는 추세입니다.

파이어폭스는 새로운 3.5 버전을 출시하며 기존 3.0 버전과 세대 교체를 이뤄왔으나 올초에 다소 기세가 꺾이는 모습을 보여주었습니다. 같은 시기의 기타 브라우저(Other)의 점유율 상승과 연관지어 볼 때, 아마도 구글 크롬의 반격으로 인한 효과가 아닌가 생각해봅니다.

How to manage high multiple servers?

There are two methods of expanding your KVM switch installation by adding additional KVM switches and thereby greatly increasing its overall capacity; cascading and daisy chaining.

Cascading

Cascading KVM switches is a method of adding capacity to a KVM installation. It involves using a CPU port of the Parent KVM switch (one that is above a switch linked down from it) and connecting to a Child KVM switch. With numerous Child switches linked down from the Parent, the effect is reminiscent of the way water cascades down over a waterfall. Cascading can significantly increase the number of computers on an installation, however the Parent switch loses one CPU port for each cascaded KVM switch that is added.

Daisy Chaining

Daisy chaining is another method of expanding the capacity of a KVM switch installation. In a simple daisy chained installation, KVM switches are strung together in a chain similar to the way children make chains of daisies by tying the head of one daisy to the end of another. The first daisy chained KVM switch is called the Master unit and each subsequent unit on the chain is referred to as a slave. In a typical daisy chained installation, the total number of consoles is increased as the number of units daisy chained increases. The console that belongs to the Master KVM unit can also access and control all of the computers down the daisy chain installation. Daisy chaining preserves CPU ports by using Chain In and Chain Out ports to attach each daisy chained KVM switch.