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system:ip_addresses

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IP Addresses

IPv4 addresses (this host and subnet):
208.96.15.248/29 network:
208.96.15.248 network
208.96.15.249 Default Gateway
208.96.15.250 HSRP
208.96.15.251 HSRP
208.96.15.252 SF-LUG (sf-lug.com., etc.)
208.96.15.253 (useable - reserved for future use(?))
208.96.15.254 for BALUG use
208.96.15.255 broadcast

Note that 208.96.15.254 is principally reserved for BALUG use. Services that aren't BALUG's or conflict or potentially conflict with what BALUG wishes to use on port(s) on that IP may get "bumped" from that IP address (e.g. the non-BALUG service reconfigured so it doesn't run or also run on that IP). Note also that in some/many cases BALUG may have no objection or conflict with some common services not specific to BALUG also running on 208.96.15.254 (so those may simply peaceably coexist and not or not likely be "bumped" off of that IP).

Some background/references/excerpts on the IPv4 addresses follows:
Notes re 2007-04-16 SF-LUG meeting about the colo box Cc: nathank From: jim stockford Subject: Re: IP addresses Date: Mon, 23 Apr 2007 08:52:11 -0700 To: Michael Paoli   hi, michael, note i've copied nathan.   Take 254. thank you for the explanation.   On Apr 22, 2007, at 7:03 PM, Michael Paoli wrote:   > Well, ... let me/us know if we can snag one of those IPs for BALUG. > > Looks like we've got a network of 208.96.15.248/29: > 208.96.15.248 network > 208.96.15.249 Default Gateway > 208.96.15.250 HSRP > 208.96.15.251 HSRP > 208.96.15.252 sf-lug.com. > 208.96.15.253 (useable) > 208.96.15.254 (useable) > 208.96.15.255 broadcast > > ... so, ... could potentially use 208.96.15.253 or 208.96.15.254 > for BALUG (perhaps 208.96.15.254) if you might want to keep the other > available IP contiguous with the existing sf-lug.com. IP). > > Typically on a /29 there would be 5 useable IPs (8 less 2 for network > and > broadcast less one more for router) ... but with HSRP that drops us to > 3 useable (HSRP using n+1 - two routers, that's 3 IPs - one for each > router + one high availability virtual IP to serve as the default > route). > > At best, if we want to maintain high availability routing, we might be > able to squeeze one more IP out of them ... but anything beyond that > and > we'd have to sacrifice any router redundancy. Since the only "box" we > have on the subnet is the LINUX box, and it's quite capable of being > configured with two default routes (and will use whichever one works), > going without HSRP, and instead just having the two IPs for the two > routers > would work as well in terms of high availability routing ... but this > may > not be standard operating procedure for the colo, so they may or may > not > be particularly agreeable to making such a change. In any case, that > would > only gain us one additional useable IP - bringing us from 3 up to 4. > > Squeezing a 5th IP would generally mean sacraficing router/routing > failover. > > http://en.wikipedia.org/wiki/Hot_Standby_Router_Protocol > http://tools.ietf.org/html/rfc2281 > > Quoting jim stockford: > >> Here's a clip from the ServePath Network >> Team. >> Check it out: >> >> You have been assigned the following block of IP addresses: >> >> First Useable IP address: 208.96.15.252 >> Last Useable IP address: 208.96.15.254 >> Default Gateway: 208.96.15.249 >> Netmask: 255.255.255.248 >> >> DNS 216.93.160.16 >> DNS 216.93.170.17 >> >> You are assigned power ports 248.8.10 >> >> Please note that your VLAN is implemented with HSRP for >> redundancy. This is why the first 3 useable IP addresses of <---- >> your IP block are reserved and not useable.

system/ip_addresses.1177882347.txt.bz2 · Last modified: 2007-04-29T21:32:27+0000 by 198.144.194.236