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Toe Rag posted:If VLSM confuses you it's cos you're thinking too much into it. Subnetting a /24 is no different than subnetting a /26 and so on. Just ignore the fact that there is already a subnet existing. Here is a perl script I found some time ago that will help you visualize it: http://67.183.123.233/ipcalc Thanks for that. I worked with it for a little bit and cleared things up a little. I probably am overthinking it too, our instructor used a visual to explain VLSM (Taking a box, then splitting it down for the subnets) and it made sense, but doing it on my own didn't. I'll work with it some more and figure it out.
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Dec 4, 2008 22:00
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I never really 'got' it until I spent the better part of an afternoon with a whiteboard and some dry erase markers, drawing the thirty-two individual bits of an address and a mask. Forget even doing the binary conversion at that point, just focus on seeing how the CIDR notation is referring to the bits of the mask, and how many bits left you have (that aren't masked) to play with. This might also be a good time to learn how to count in binary if you want. Of course nowadays, I just use this hilarious flash based subnet calculator I found, that looks like something from Planescape Torment: http://www.warriorsofthe.net/utils/index.html
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Dec 5, 2008 05:19
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For me, it was one of those things that didn't "click" until I just started doing it everyday in my job. It was kind of a "use it or lose it" deal, so when I started doing a lot of design and core ISP route troubleshooting it became second nature. Now everything I do is not really bigger than /24s and very flat, I feel a bit rusty. jwh has it though, just take a day with a whiteboard, have another engineer put up problems and subnetting questions and just work through them. I had a cisco instructor show me a way to do it with circles and cutting it up, but I can't find it online, he mentioned "try to get a patent on it" so who knows. Most of the time I just use Solarwinds Advanced Subnet Calc, its free as well.
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Dec 5, 2008 14:04
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jwh posted:I never really 'got' it until I spent the better part of an afternoon with a whiteboard and some dry erase markers, drawing the thirty-two individual bits of an address and a mask. This is essentially how I mastered subnetting. Once you draw it all out, you can visualize it better and get faster. That, and I had this helpful little aid: code:
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Dec 5, 2008 18:14
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I'm starting to poke around in Packet Tracer to see what I can work out without formal training, and there's one thing that I can't seem to work out. I have a few PC's with addresses 192.168.1.2 to .5 and connected to a switch. I have that connected to a router with one interface configured to be 192.168.1.1 I have another few PC's with the same statically assigned addresses of 192.168.2.2 to .5, connected to a switch. I have connected that switch to the second router interface configured to 192.168.2.1 As that stands, everything is awesome and they can all speak to each other and I don't feel like a total 'tard. But what happens when I want to introduce a third subnet? I'm just not entirely sure on the logical topology on a larger-than-bedroom network!
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Dec 7, 2008 22:22
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Jagtpanther posted:I'm starting to poke around in Packet Tracer to see what I can work out without formal training, and there's one thing that I can't seem to work out. Well, what does the third subnet connect to? That's really what will determine everything else. And by that I mean, are you imagining another router, or another interface on an existing router? There's a number of ways you can go here. Try restating the problem, first, because I'm not entirely clear as to what you're trying to work out.
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Dec 8, 2008 05:23
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I have an ASA 5505 at a remote site that I am having a bit of an issue with. I only have the base 10 user license, but at the same time there are only a total of 7 ip hosts in the office. Ive got a couple hosts inside that are refusing to talk outside that remote LAN. The ASA shows that all 10 licenses are in use and syslog is telling me it is denying connections based on number of licenses being exceeded. I SSHed into the device and ran clear xlate but I can't seem clear up the number of used licenses. What am I missing here? EDIT: I had a user at the remote site power cycle the device and it is now working properly. Does clear xlate not clean up licensing issues? Syano fucked around with this message at 22:09 on Dec 10, 2008 |
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Dec 10, 2008 20:50
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I need a small favor from a CCIE (or someone will access to that level on the website) if anyone has a minute. I will send you a nice Christmas present if you can help. PM or IM me. Thanks!
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Dec 12, 2008 19:57
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Any 15454 guys around? My company ordered a bunch of VT1.5 circuits that come to us through an OC-12. The equipment they go to only takes M23/cbit framed DS3s. My supplier only has DS3XM-6 cards and I'm having trouble finding a data sheet on them, the only concrete thing I have right now is from cisco's site and states that they only do M13 framing. quote:The Cisco ONS 15454 DS-3 Transmultiplexer card, commonly referred to as the DS3XM-6 transmux card, provides six, Telcordia-compliant (GR-499-CORE), M13 interfaces. The DS3XM-6 converts each framed DS-3 network connection to 28 VT1.5s mapped to an STS-1 that then interface to the cross-connect card. The DS3XM-6 card works in conjunction with a Cisco ONS 15454 VT-compatible cross-connect card allowing the VT1.5 traffic to be switched/groomed to optical and electrical VT-compatible line cards. What I was thinking of doing was mapping the VT1.5s to a port on the transmux card then mapping the STS-1 to a DS3-12 card that goes to my existing equipment. I just want to make sure that this is possible without having to externally loop. So an example circuit on the following hypothetical 454: s1 = DS3 s3 = DS3N s6 = Working OC-12 s7-11 = XCVT/TCC s7 = Protect OC-12 s15 = DS3XM-6 (protect) s17 = DS3XM-6 Say s6/p1/S1-11 are mapped to ports s1/p1-11 as regular STS-1 cross connects. For s6/p1/S12 which would have VT1.5 circuits it's possible to build the following circuits: s6/p1/S12/V1-1 to V7-4 -> s17/p7/S1/V1-1 to V7-4 ( OC-12 to VT xconnect ports ) s17/p8/S1 to s1/p12/S1 ( STS cross connect to DS3 card) The end result would be a M23 framed DS3 coming out of port 12 on the DS3 card holding the VT1.5 circuits as T1s. With internal cross connect magic turning the 28 VT1.5s on p7/S1/Vx-x into STS-1 p8/S1. Right now what I have is the STS-1 on the OC-12 mapped to a regular port on a DS3-12. I assumed that was broken because I wasn't seeing the circuit come up but I just noticed I'm getting unequipped path on that slot. Could this be caused because of how I'm mapping the circuit? Since I can't find a data sheet or much info on the DS3XM-6 so I'm using what is around for the DS3XM-12 and adapting. Are there any other major differences other then port count and DS3 framing type?
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Dec 14, 2008 03:02
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Quick question: I recently inherited a used Cisco 7200 router at work, however I'm having a hell of a time getting this thing to save it's config-register after I cleared out the old running config. Basically the thing is not recognizing the straight forward task of seeing that the running config has a config-register of 0x2102, not 0x2142. After saving the config after changing the pw, and then reloading the router, my prompt always says: routername(boot)> If I make any changes to the running config and save them, they appear after a restart, so I'm assuming that it is recognizing that it has the right config register set, even sh version tells me that: Cisco Internetwork Operating System Software IOS (tm) 7200 Software (C7200-BOOT-M), Version 11.3(2)AA, EARLY DEPLOYMENT, RELEASE SOFTWARE (fc1) Copyright (c) 1986-1998 by cisco Systems, Inc. Compiled Mon 02-Mar-98 16:21 by rnapier Image text-base: 0x600088C4, data-base: 0x60466000 ROM: System Bootstrap, Version 11.1(10) [dschwart 10], RELEASE SOFTWARE (fc1) NOTBOOT uptime is 4 minutes System restarted by power-on Running default software cisco 7204 (NPE150) processor with 26624K/6144K bytes of memory. R4700 processor, Implementation 33, Revision 1.0 (512KB Level 2 Cache) Last reset from power-on Bridging software. X.25 software, Version 3.0.0. 1 FastEthernet/IEEE 802.3 interface(s) 125K bytes of non-volatile configuration memory. 1024K bytes of packet SRAM memory. 16384K bytes of Flash PCMCIA card at slot 0 (Sector size 128K). 4096K bytes of Flash internal SIMM (Sector size 256K). Configuration register is 0x2102 What's goin on here?  I mean, I guess nobody wanted it for a reason...
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Dec 21, 2008 20:05
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Wicaeed posted:Quick question: Output of "dir flash:"? You've "copy run start" I assume and it reports back all ok? Can you paste the output from a power on until the "routername(boot)>" ?
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Dec 22, 2008 01:02
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Try changing the config register from rommon instead of the config. http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a008022493f.shtml#set-config-rommon Of course an NPE150 could be a decade old, it may just be insane.
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Dec 22, 2008 01:04
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I'll give this a try when I get into work tomorrow, thanks
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Dec 22, 2008 06:47
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inignot posted:Try changing the config register from rommon instead of the config. NPE150 is stupid old. We won't use anything lower than an NPE400, and even then I'm wishing it was a NPE-G1.
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Dec 22, 2008 09:29
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GOOCHY posted:Just to wrap up this weird one - I downloaded the Cisco TFTP server released in 1995 and hosted on oldversion.com and it worked immediately. Note to self - Solarwinds TFTP server acts funky from time to time... do you(or anyone else here for that matter), know of a free tftp server alternative to Solarwinds? I'm having the same problem where I try to copy something over and their tftp server shuts down. e: and other than the old cisco one, that one made me pretty angry a few times to. coconono fucked around with this message at 17:20 on Dec 22, 2008 |
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Dec 22, 2008 17:15
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FatCow posted:Any 15454 guys around? Well you've probably already figured this out, but anyway. The XM-6 transmuxes a VT1.5 mapped STS1 to an M13/M23 DS3. The XM12 does the same thing but offers some additional features, like portless transmux (the original XM6 would only connect the M13 mapped DS3 to a backplane port, with the XM12 you can map it to a DS3 in an STS1 so you can connect to a regular DS3-12 or DS3-48 port on another shelf), and obviously higher port density. So in your case if you don't have a B side EIC you'll either need to get one, or move your XM6 to the 1-6 side of the shelf. Alternately if you get an XM12 and you have an OC48 anyslot shelf (an ANSI or above, as well as a 10G XC card) you could portless transmux like you described above. Path unequipped generally means there's nothing built on the other side of the OCx connection, in this case if you're seeing it at a VT level it could be because you're on the wrong vt group/vt combination, there are 2 standards for doing channel->vt mapping, if you don't have these charts I can probably dig up a copy to post here... coconono posted:do you(or anyone else here for that matter), know of a free Solarwinds alternative? I'm having the same problem where I try to copy something over and their tftp server shuts down. tftpd32 or if your code is really big (128M+) you may need to use another transport since tftp shits its pants on large files, we'll usually use HTTP or RCP... ragzilla fucked around with this message at 17:21 on Dec 22, 2008 |
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Dec 22, 2008 17:19
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coconono posted:do you(or anyone else here for that matter), know of a free tftp server alternative to Solarwinds? I'm having the same problem where I try to copy something over and their tftp server shuts down. Seconding tftpd32. That's my primary Windows TFTP server, all my tech laptops are loaded with it for recovering retarded Aastra phones. I'm indifferent between tftpd-hpa and atftpd on Linux.
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Dec 22, 2008 20:38
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Wicaeed posted:Quick question: I was playing around with a 7500 this weekend and had the exact problem after swapping out RSP cards. Here is what worked for me and might help you out as well. I had to go in config t and type in "boot system (in my case) slot0:ios-image-here.bin" and have it boot from the IOS image that was stored on the PCMCIA card. I imagine you will have to do something similar to this and you will get it back up. -edit- You can also do a "Show Bootvar" and see where it is looking for the IOS image Magwai fucked around with this message at 20:51 on Dec 22, 2008 |
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Dec 22, 2008 20:46
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Can anyone tell me about the 2960 switches with the LAN Lite image? We normally use Catalyst Express 500s, but these are comparable in price and at first glance, seem to have a better feature set. Our clients can't afford to shell out for a full blown 2960.
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Dec 24, 2008 17:38
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ragzilla posted:The XM-6 transmuxes a VT1.5 mapped STS1 to an M13/M23 DS3. The XM12 does the same thing but offers some additional features, like portless transmux (the original XM6 would only connect the M13 mapped DS3 to a backplane port Ugh, my PM isn't going to be happy when I go to install these guys. I talked with our equipment vendor and they assured me that the XM-6s could do portless stuff. I think this will be the final nail in their coffin.
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Dec 31, 2008 01:30
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Richard Noggin posted:Can anyone tell me about the 2960 switches with the LAN Lite image? We normally use Catalyst Express 500s, but these are comparable in price and at first glance, seem to have a better feature set. Our clients can't afford to shell out for a full blown 2960. I think the major differences are IP6 and number of supported VLANs. This link seems helpful: http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps6406/prod_qas0900aecd80322c37.html edit: I feature compared 12.2(46)SE LAN Base with 12.2(46)SE LAN Lite, and the features unique to Base are: DHCP Snooping DHCP Snooping Counters Flex Link VLAN Load-Balancing Flex Links Interface Preemption IEEE 802.1x - Auth Fail VLAN IEEE 802.3af PoE (Power over Ethernet) IP SLAs - SNMP Support IP SLAs Responder IPv6 Default Router Preference Lock and Key MLD Snooping Trunk Failover Although I suspect that list isn't comprehensive. jwh fucked around with this message at 18:26 on Dec 31, 2008 |
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Dec 31, 2008 18:03
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FatCow posted:Ugh, my PM isn't going to be happy when I go to install these guys. I talked with our equipment vendor and they assured me that the XM-6s could do portless stuff. I think this will be the final nail in their coffin. Hey, let me know if you need to sell the XM-6s you already have. Actually I may be able to help with the 12s too. I had no idea previously that 6s didn't do portless. This thread teaches me something new every day. Thanks ragzilla!
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Dec 31, 2008 19:04
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I called my vendor and yelled at them for guessing instead of trying things in their lab and got them to overnight me some BNC backplates. Luckily I didn't fly out to install these things yet. I dug into the M13/M23 issue and both DS3-12s and DS3XM-6s seem to have the same standards for output so I'm hoping I'll be good with that. Has anyone used the new "e100" (maybe ml100?) cards that drop you to some kind of IOS prompt? I was on the phone with XO last night and they are using these things and the tech couldn't figure out how to throw me a loop.
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Jan 1, 2009 00:52
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jwh - I sent you a PM about this, but maybe some of the other cisco thread readers can help too: I'm looking at getting a 16 or 48 port serial console server, and in the past we've been using a portmaster for our colo (lovely), and Lantronix SCS devices for remote sites. I haven't been too happy with the SCS devices as they tend to be annoying to configure. In your opinion what's better - the Avocent Cyclades ACS48, the CS4016, or the Lantronix SecureLinx series? Have you had any experience with the HP console server?
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Jan 1, 2009 01:16
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I have got an ASA 5510 with the CSC SSM installed that is freaking out. The ASA itself it sitting right aroung 85% memory usage and climbing. The CSC SSM is even higher and last night delivered a failure to download virus defs, which is the first time it has even done that. Then this morning, it emails me and says I am in liscense violation to the tune of oh about 134 MILLION licenses. Um, what is this thing doing?
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Jan 1, 2009 17:28
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Magwai posted:Here is what worked for me and might help you out as well. I had to go in config t and type in "boot system (in my case) slot0:ios-image-here.bin" and have it boot from the IOS image that was stored on the PCMCIA card. I imagine you will have to do something similar to this and you will get it back up. A technical description for those who are interested is that you're using the bootloader firmware (which is a very cut-down feature-wise version of your image) which resides on bootflash, not the full image. You can have multiple boot system commands (where if one fails, it tries the other) - this is useful if something happens to your flash and you still want it to boot from your bootflash as opposed to getting stuck in ROMMON. Wicaeed - what are your plans with that 7200? 32MB memory won't go very far, certainly with what these things are capable of. I'd strongly suggest getting your hands on some third party RAM (the 150 maxes out to 128MB) which'll permit you to run some newer images. The 7200 platform is very nice (I've collected quite a few in my travels) and I had one as my home router before I replaced it with a 2851. Your current image is quite dated and is vulnerable to all sorts of nasty poo poo. Now, question for y'all. Has anybody here seen stack port flaps (up/downs) on the Catalyst 3750 switches? We've got over 1500 in production and we've found we're getting this happen about 2-4 times a month. Sometimes the whole stack goes crazy and reloads. A hardware replacement of the affected switch has solved the problems prior and we have a TAC case/EFA in progress. We can't possibly be the only organisation seeing this.
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Jan 1, 2009 17:50
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evilZardoz posted:Now, question for y'all. Has anybody here seen stack port flaps (up/downs) on the Catalyst 3750 switches? We've got over 1500 in production and we've found we're getting this happen about 2-4 times a month. Sometimes the whole stack goes crazy and reloads. A hardware replacement of the affected switch has solved the problems prior and we have a TAC case/EFA in progress. We can't possibly be the only organisation seeing this. We have seen them crash on their own and reload, and since the drat things take forever to boot up we do hear about it, but there hasn't been anything we can do. I haven't seen any of them actively disrupt a stack continuously warrenting replacement for just that reason, but I have noted that depending on how it is set up, if you have loops and other errors that it is monitoring for recovery, it may eventually run out of memory and poo poo itself.
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Jan 1, 2009 18:10
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evilZardoz posted:Now, question for y'all. Has anybody here seen stack port flaps (up/downs) on the Catalyst 3750 switches? We've got over 1500 in production and we've found we're getting this happen about 2-4 times a month. Sometimes the whole stack goes crazy and reloads. A hardware replacement of the affected switch has solved the problems prior and we have a TAC case/EFA in progress. We can't possibly be the only organisation seeing this. You aren't. I've got no issues with standalone 3750's; they've been pretty reliable for me in the past actually. But as soon as anyone decides to stack them, that's when the problems start. I hate 3750 stacks  I've seen all kinds of crazy poo poo happen with stacks - the real fun ones are when you've got a 2-switch stack providing connectivity to a rack of servers and the stack decides to go tits up to the point where you've got this weird split-brained situation where each switch is still being seen by IOS as a "stack member" but they're making their own independent forwarding decisions. When we see stack port flaps we generally start by replacing the StackWise cables. If that doesn't help then we RMA both switches. 
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Jan 2, 2009 01:27
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atticus posted:You aren't. I've got no issues with standalone 3750's; they've been pretty reliable for me in the past actually. But as soon as anyone decides to stack them, that's when the problems start. I hate 3750 stacks Completely anectdotal, but have you ever had issues with the 3750Es in stacking or standalone format? I have never had issues with them, but standard 3750s I have seen stack flaps several times.
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Jan 2, 2009 20:41
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So what do you guys use for serial console servers?
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Jan 2, 2009 22:38
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CrazyLittle posted:So what do you guys use for serial console servers? Ive had good luck with Cyclades ACS16 servers, but they're a bit pricy.
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Jan 2, 2009 22:57
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CrazyLittle posted:So what do you guys use for serial console servers? My current job uses old 2500s off Ebay. Prior job used these things: http://www.commdevices.com/products/encryption/pa-44.html
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Jan 3, 2009 04:24
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jbusbysack posted:Completely anectdotal, but have you ever had issues with the 3750Es in stacking or standalone format? I have never had issues with them, but standard 3750s I have seen stack flaps several times. You know, I'll have to dig through syslog to see. We started deploying the E's as top-of-rack switches about a year ago, two per stack. I'll let you know.
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Jan 3, 2009 11:49
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CrazyLittle posted:So what do you guys use for serial console servers? I forgot to check which Avocents we had- but like I had mentioned earlier, I'm a big fan of the Lantronix SLC boxes.
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Jan 3, 2009 19:11
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Ebay'd 3620s with 32 port async cards. [edit] Can't use 2 unless you only want modem/console access. FatCow fucked around with this message at 03:18 on Jan 4, 2009 |
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Jan 4, 2009 02:55
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jbusbysack posted:Completely anectdotal, but have you ever had issues with the 3750Es in stacking or standalone format? I have never had issues with them, but standard 3750s I have seen stack flaps several times. 3750Es are totally different beasts. They use "stackwise+" Which aside from being a marketing term has 64GB bandwidth as well as protection similar to "BLSR" . The E series of switches are really awesome and it wouldn't surprise me if it fixed those problems. 3750's have been around for a long time, and are just generally old switches. Of course the price premium for a stack of E's is "significant."
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Jan 4, 2009 04:23
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Powercrazy posted:3750Es are totally different beasts. They use "stackwise+" Which aside from being a marketing term has 64GB bandwidth as well as protection similar to "BLSR" . The E series of switches are really awesome and it wouldn't surprise me if it fixed those problems. My problem with the E-series aside from cost is that afaik you cant get a switch that will put out 18.4mW or whatever the 1252 802.11n APs need on PoE. Daisy-chaining injectors isnt a particularly good solution either. Correct me if im wrong about the PoE capabilities of other devices though, I'd be interested in hearing about them. That said, a couple X2 10G modules are super for bladecenter chassis uplinks.
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Jan 4, 2009 06:21
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jbusbysack posted:My problem with the E-series aside from cost is that afaik you cant get a switch that will put out 18.4mW or whatever the 1252 802.11n APs need on PoE. Daisy-chaining injectors isnt a particularly good solution either. Correct me if im wrong about the PoE capabilities of other devices though, I'd be interested in hearing about them. quote:That is why Cisco developed Cisco Enhanced PoE, Cisco's extension to the IEEE 802.3af standard that delivers as much as 20W per port of inline power for devices that support Cisco Discovery Protocol (CDP). Cisco Enhanced PoE is offered on Catalyst 3750-E and Catalyst 3560-E switches starting in February 2008 with Cisco IOSŪ Software Release 12.2(44)SE. The Catalyst 6500 Series10/100/100 PoE linecards support Enhanced PoE with 12.2(33)SXH2 or later and the Catalyst 4500 E-Series support Enhanced PoE with 12.2(44)SG or later. From here. http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/White_Paper_C11-453743-00.html Basically wait about 2 months and your 3750-Es will support the new 802.11n APs.
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Jan 4, 2009 08:04
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Powercrazy posted:From here. http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/White_Paper_C11-453743-00.html Yeah, I'm sorry - mistyped. My issue is that no other device besides the -E series will do enhanced PoE when that class of switch is complete overkill for your typical access port/WAP needs.
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Jan 4, 2009 08:40
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jbusbysack posted:Yeah, I'm sorry - mistyped. My issue is that no other device besides the -E series will do enhanced PoE when that class of switch is complete overkill for your typical access port/WAP needs. Well the idea is that if you are running a full wireless mesh infrastructure it is assumed you have wiring closets and have drops running to cubicles etc. Thus you will have either a small stack of 3750s, or a 4500 or 6500 chassis. Where else would you want to run n APs? Also its definitely a selling point, want to support n APs? Then you need the new top of line switches. The E's also support full line rate GigE which is pretty cool.
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Jan 4, 2009 19:42
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