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Cisco IOS feature software
- Thread starter me19562
- Start date
When you boot up the router, it posts the version and feature codes on the startup banners (you must be connected to the console port).
I believe you can see them in the ROM monitor mode as well (where you'd add the keys to enable features, like Crypto).
Good Luck
Scott
I believe you can see them in the ROM monitor mode as well (where you'd add the keys to enable features, like Crypto).
Good Luck
Scott
there are two characters in the IOS file name, you can see with a "show ver" that will tell you the feature set installed and the file used to boot.
Check here for a complete run down...
http://www.cisco.com/cgi-bin/Support/CompNav/Index.pl?&SoftwareType=True
Check here for a complete run down...
http://www.cisco.com/cgi-bin/Support/CompNav/Index.pl?&SoftwareType=True
ME15962:
What is it you're trying to do?
If all the VLANs are going to servers (or mostly to servers), then drop in an 802.1q/ISL-enabled NIC in the servers. Each VLAN appears to be its own logical NIC, and you don't suffer the bottlenecks of the one-armed routing scenario.
Depending on which switches/routers you have, you may be able to use MLS (much quicker/less bottleneck).
If you're in the mood, give us a brief rundown of what you'd like to do....we haven't had a good religeous topology argument in a long time....(just kidding). Spidey, Garion, L3Guy, and others are an excellent source for network design recommendations.
FWIW
Scott
What is it you're trying to do?
If all the VLANs are going to servers (or mostly to servers), then drop in an 802.1q/ISL-enabled NIC in the servers. Each VLAN appears to be its own logical NIC, and you don't suffer the bottlenecks of the one-armed routing scenario.
Depending on which switches/routers you have, you may be able to use MLS (much quicker/less bottleneck).
If you're in the mood, give us a brief rundown of what you'd like to do....we haven't had a good religeous topology argument in a long time....(just kidding). Spidey, Garion, L3Guy, and others are an excellent source for network design recommendations.
FWIW
Scott
Originally posted by: spidey07
All 12.x versions that I know of.
Depends greatly on hardware though and not software. And as a second thought...don't do it. bad design.
One-armed routers are a thing of the past.
Mind describing the "one-arm router" and what's so bad about it? I've never heard of that term before.
Originally posted by: ScottMac
If all the VLANs are going to servers (or mostly to servers), then drop in an 802.1q/ISL-enabled NIC in the servers. Each VLAN appears to be its own logical NIC, and you don't suffer the bottlenecks of the one-armed routing scenario.
Depending on which switches/routers you have, you may be able to use MLS (much quicker/less bottleneck).
If you're in the mood, give us a brief rundown of what you'd like to do....we haven't had a good religeous topology argument in a long time....(just kidding). Spidey, Garion, L3Guy, and others are an excellent source for network design recommendations.
FWIW
Scott
What is MLS? Can you explain how the use of ISL/802.1q NICs in the servers bypasses the one-arm router problem? I thought you'd still need an uplink (trunk) to a router in order for the VLAN to be routed?
No Problem....
When you are using VLANS, you're basically sending several subnets down the same cable/segment. VLANS are completely separate and discreet information flows (broadcast domains). Like any net-to-net or subnet-to-subnet communication, the only way to get information from one VLAN to another is to route it.
Since you are basically only running one cable to the router (with multiple VLANs on that cable), it was termed a "One Arm Router" (actually a term that came from the ol' ATM days with ELAN to ELAN routing). Cisco likes to call it "Router on a stick" because the Cisco Icon is a circle, and the line drwan up to it makes it look like a lollipop (on paper).
A router acting as a "one arm router" can (usually does) support other connections at the same time, but for the purposes of discussion, it's usually talked about as one trunked connection to the router (packets come in on one VLAN, and leave on another, but stay on the same trunked connection). Packets can be routed from a VLAN on the trunk to other trunks or discreet subnets.
My comment about using an 802.1q or ISL NIC in the server is sort of the same thing. When you install and configure a VLAN-enabled NIC in the server, you install a single PHYSICAL NIC. When you enable 802.1q or ISL on that NIC, the drivers make it appear as multiple LOGICAL NICS, one for each VLAN you define. The effect is that you have (for example) four physical connections going to four physical NICs in the server .... making the server appear as a local host on that subnet / VLAN (the ideal setup is zero-hop to the resource, if possible).
MLS is Cisco-speak for "Multi-Layer Switching." With the proper router/switch combination, a packet needing to cross VLANs (needs to be routed) is sent from the switch to the designated router for routing. The switch keeps track of the packet to see where it came from, and where it's going. When it comes back from the router, the switch confirms the destination, then places all the information in a table (CAM).
The next time a packet from the same source going to the same destination comes into the switch, instead of sending it to a (slow) router, it just changes what needs to be changed, and switches it on to the destination ... much faster (wire speed) than routing. There are several variations, but the basic premise is "Route the first packet, switch the rest." The process can be cranked down to where a packet from the same source, same destination, same socket/port (a packet port, like 23 = telnet) get's it's own entry in the CAM. It can also be "loosened up" to the point where any packet from the same source going to the same destination gets an entry. A threshold can be set so that infrequent flows do not get MLS switched.
Graphics would help a lot. If it's still not clear, check out MLS at Cisco's web site.
FWIW
Scott
When you are using VLANS, you're basically sending several subnets down the same cable/segment. VLANS are completely separate and discreet information flows (broadcast domains). Like any net-to-net or subnet-to-subnet communication, the only way to get information from one VLAN to another is to route it.
Since you are basically only running one cable to the router (with multiple VLANs on that cable), it was termed a "One Arm Router" (actually a term that came from the ol' ATM days with ELAN to ELAN routing). Cisco likes to call it "Router on a stick" because the Cisco Icon is a circle, and the line drwan up to it makes it look like a lollipop (on paper).
A router acting as a "one arm router" can (usually does) support other connections at the same time, but for the purposes of discussion, it's usually talked about as one trunked connection to the router (packets come in on one VLAN, and leave on another, but stay on the same trunked connection). Packets can be routed from a VLAN on the trunk to other trunks or discreet subnets.
My comment about using an 802.1q or ISL NIC in the server is sort of the same thing. When you install and configure a VLAN-enabled NIC in the server, you install a single PHYSICAL NIC. When you enable 802.1q or ISL on that NIC, the drivers make it appear as multiple LOGICAL NICS, one for each VLAN you define. The effect is that you have (for example) four physical connections going to four physical NICs in the server .... making the server appear as a local host on that subnet / VLAN (the ideal setup is zero-hop to the resource, if possible).
MLS is Cisco-speak for "Multi-Layer Switching." With the proper router/switch combination, a packet needing to cross VLANs (needs to be routed) is sent from the switch to the designated router for routing. The switch keeps track of the packet to see where it came from, and where it's going. When it comes back from the router, the switch confirms the destination, then places all the information in a table (CAM).
The next time a packet from the same source going to the same destination comes into the switch, instead of sending it to a (slow) router, it just changes what needs to be changed, and switches it on to the destination ... much faster (wire speed) than routing. There are several variations, but the basic premise is "Route the first packet, switch the rest." The process can be cranked down to where a packet from the same source, same destination, same socket/port (a packet port, like 23 = telnet) get's it's own entry in the CAM. It can also be "loosened up" to the point where any packet from the same source going to the same destination gets an entry. A threshold can be set so that infrequent flows do not get MLS switched.
Graphics would help a lot. If it's still not clear, check out MLS at Cisco's web site.
FWIW
Scott
Perfectly clear. Great explanation.
I was always under the impression you had to have one physical trunk (uplink) to the router for each VLAN. I guess that idea came from the 1900s not having ISL/802.1q available. Come to think of it, how do the 1900s deal with VLANs?
When you put the trunking capable NIC in the server I assume it creates separate protocol bindings for each logical NIC?
I was always under the impression you had to have one physical trunk (uplink) to the router for each VLAN. I guess that idea came from the 1900s not having ISL/802.1q available. Come to think of it, how do the 1900s deal with VLANs?
When you put the trunking capable NIC in the server I assume it creates separate protocol bindings for each logical NIC?
Yes, correct. Each logical NIC (may be) is allowed its own binding/protocol. So, maybe you have part of the organization running Novell over IPX and the rest have been migrated to IP-Only. Each of those could be a seperate VLAN instance on the server.
Kinda cool, ain't it? Technology is a wunnerful thing......
FWIW
Scott
Kinda cool, ain't it? Technology is a wunnerful thing......
FWIW
Scott
ok, everything start playing with my lab in my work(3 2610, 1 2948G and 1 2924XL) then i found that the 2610 don't support trunking. I just wanted to setup a few vlans in the switches and make the routing with the router to test and if all worked fine then make the setup in the network with a 7202 with 2 fastethernet int in etherchannel and trunking connected to a Cat 6006, but anyway i found that 7202 don't support trunking too. Well I gonna have to wait until I can justify and MFSC for the 6006. Guys know about the snmp vulnerability in IOS. I check and supposedly Cisco is giving the fix free that i believe IOS 12.0(22), but that apply for any IOS version?
thx for the feedback guys
thx for the feedback guys
only fast ethernet interfaces support trunking and can generally only tag with ISL.
7200 does trunking just fine with a PA-FE
you'll need a 2620 to do trunking. I've done it before in VERY EXTREME CASES WHERE I ABSOLUTELY HAD TO.
ps - If you need to route and you don't have a MSFC for that 6006. Well, you need to get one. end of story, end of justification, however you are trying to sell this to MUST get a MSFC. wire speed routing for cheap. Your 7000 dreams of keeping up with a MSFC. We're talking 300,000 PPS vs 15,000,000 PPS i believe.
7200 does trunking just fine with a PA-FE
you'll need a 2620 to do trunking. I've done it before in VERY EXTREME CASES WHERE I ABSOLUTELY HAD TO.
ps - If you need to route and you don't have a MSFC for that 6006. Well, you need to get one. end of story, end of justification, however you are trying to sell this to MUST get a MSFC. wire speed routing for cheap. Your 7000 dreams of keeping up with a MSFC. We're talking 300,000 PPS vs 15,000,000 PPS i believe.