On Thu, Apr 27, 2023 at 2:38 PM, Adam Thompson <[email protected]> wrote:
> Fascinating. I’ve never had an ASR-1001 come with two sets of ears, and I > also note that the text of the instruction manual doesn’t reference the > rear set at all. I’ve never seen rear ears on any Cisco gear of my own, > nor on anything the local ILEC has installed either. I think the diagram > is in error here. > > However, the “optional” step 1 is a pretty solid hint (i.e. pretty much a > clue-by-four upside the head, here!) that you really should use a shelf. > As in you REALLY SHOULD USE A SHELF of some kind. > Hah! Your mention of clue-by-fours while we are talking about drooping routers reminds me of one of my more useful tools. I have a bunch of bits of 2x4 which I've cut to around 1.75", 3.5", 7". These are really really helpful when trying to mount a piece of equipment under something which is either not screwed in, or is drooping at the back. You can use these as spacers when replacing a bit of gear which is supporting other bits of gear, or, with a small shim/flat screwdriver as a way to jack up a devices which is drooping at the back (and so slide in another device). There are much more elegant solutions (like a machinist jack), but a few off-cuts of 2x4 are cheap, light, and non-marring. This thread feels somewhat like "old NANOG" - people discussing actual issues that they run into, and then sharing tips and tricks to help with those issues. I miss this… W > > It doesn’t even have to be a full shelf – any rail kit that relies on an > “L”-shaped profile instead of interlocking sliding bits should support an > ASR-1001 just fine, e.g. Tripp-Lite’s 4POSTRAILKIT1U. RackSolutions’ > Universal > Fixed Server Rack Rails <https://www.rack-solutions.ca/rack-rails.html> > shows an example of a slightly different design that some prefer – it all > works about the same way. > > > > The other thing I’ve done is used a shallow cantilever shelf to support > the rear end of equipment that only comes with ears, if it’s deep enough – > something like StarTech’s CABSHELFV1U; the trick is finding a shelf that > simultaneously doesn’t have the structural fold at the rear in the way AND > doesn’t interfere with the device immediately below. You’d think there’re > only 2 geometries of product to worry about, but there are actually more > b/c there’s no standard – so test-fit first, or examine photos really > carefully. This is usually more of a hack than a permanent, supportable > solution, but sometimes it can work very well and very cheaply. > > > > Or, just make sure you’re installing the ASR immediately above something > that does have proper 4-post mounting rails. This is probably the single > most common way to safely & securely mount “eared” devices in a 4-post rack > that I’ve seen – that Dell PowerEdge server in the rack suddenly starts > doing double-duty as a shelf! (Or the UPS, or the KVM, or the ethernet > switch, or…) > > > > -Adam > > > > *Adam Thompson* > > Consultant, Infrastructure Services > > > > 100 - 135 Innovation Drive > > Winnipeg, MB R3T 6A8 > > (204) 977-6824 or 1-800-430-6404 (MB only) > > https://www.merlin.mb.ca > > Chat with me on Teams > <https://teams.microsoft.com/l/chat/0/[email protected]> > > > > > > *From:* NANOG <[email protected]> *On Behalf > Of *Chuck Church > *Sent:* Thursday, April 27, 2023 10:36 AM > *To:* 'Mark Stevens' <[email protected]>; [email protected] > *Subject:* RE: Standard DC rack rail distance, front to back question > > > > Hey all, sorry I did mean to say ASR1001 (an X model to be exact). The 4 > post mounting they show in a hardware mounting doc uses front and back > ears, which I’ve never done: > https://www.cisco.com/c/en/us/td/docs/routers/asr1000/install/guide/ > asr1routers/asr-1000-series-hig/asr-hig-1001.html#task_1205646 > see figure 16 slightly down from there. > > I do see some generic rails from TrippLite that probably would work, as > well as shelves. I was hoping a standard depth that most vendors honored > for 4 post existed, but it doesn’t seem likely. We’ll have a variety of > PaloAlto, Cisco, Checkpoint, and others co-habiting. > > > > Chuck > > > > *From:* NANOG <[email protected]> *On Behalf > Of *Mark Stevens > *Sent:* Thursday, April 27, 2023 11:17 AM > *To:* [email protected] > *Subject:* Re: Standard DC rack rail distance, front to back question > > > > Lucky you with a 19" data rack. All I have are 23" telco racks but I will > say, the 23" extension ears from Cisco are serious and my router chassis' > don't sag. > > Mark > > On 4/27/2023 10:04 AM, Chris Marget wrote: > > > > On Thu, Apr 27, 2023 at 9:53 AM Chuck Church <[email protected]> > wrote: > > for a Cisco ASA1001, there aren’t rails, but rather front and back ‘ears’ > you use to hit both front and back posts. > > > > Front *and* back ears? I'm not sure what an ASA 1001 is (ASR?) but my > experience with these boxes is that they have a single pair of ears which > can be mounted front OR back. > > The heavier / deeper 1RU devices do tend to sag alarmingly. > > > > Is there a ‘standard’ distance between front and back rails that devices > usually adhere to? > > > > If you're thinking of setting the front/back distance to accommodate a > specific device, table 2 might be of some interest: > > https://i.dell.com/sites/doccontent/business/solutions/engineering-docs/ > en/Documents/rail-rack-matrix.pdf > >
