d****i
发帖数: 1038 | 1 thanks for sharing your view.
but this should not be the reason not using it. :)
yes, it is really odd that in H-VPLS case, the upe to npe is running ldp,
but npes are running BGP. actually I am not sure how that could be
configured, especially on the npe. I am not sure how Juniper and XR support H-VPLS.
I heard there are proposals for using bgp in vpws case. If that's true, can we
use BGP to replace ldp? :)
run
But in the interAS case, BGP is needed between the two ASBR, and probably
there won... 阅读全帖 |
|
b***p
发帖数: 700 | 2 Ok, your purpose is to speed up bgp convergence to reflect uplink/node
failure. Normally there is 2 ways to achieve it, 1 is sub-second level and
another one is tens-second level.
So, let me correct your theory first. Cisco IOS default BGP timers are 60/
180, where the hold time is 180 sec. From the RFC 4271,
If a system does not receive successive KEEPALIVE, UPDATE, and/or
NOTIFICATION messages within the period specified in the Hold Time
So the total time to wait before bgp releases the ... 阅读全帖 |
|
s*****g
发帖数: 1055 | 3 Why in interAS scenario, BGP is better than LDP? as far as VPLS is concerned
, it should not care about BGP/ASBR etc, only it needs is MPLS
transportation to remote PEs, and LDP session to remote PEs to exchange L2
FECs.The issue that how to signal MPLS LSP over AS boundary is irrelevant to VPLS signaling.
I thought only Juniper is sticking to BGP VPLS, while the rest of world uses
LDP VPLS and use BGP for auto-discovery.
One obvious advantage of BGP-VPLS is that BGP has router-reflector concept... 阅读全帖 |
|
s******v
发帖数: 4495 | 4 1) BGP GR/NSF主要目的：1)HA, traff照旧，因为Fwd LC和RP都是独立，RP
switchover的同时Data Fwd不受影响；2)减少CP traf，因为BGP session reset，
withdraw会波及到所有的BGP Peers，Up之后又是新的一轮update；
2) Peering的时候BGP announce GR capability + AF/SAF，如果没有AF，Router只是
GR Awareness，但是不能perform GR，就是single RP router/或者是GR helper;
3) GR很重要的一点是可以send EOR packet; 表明所有的update完毕；
4) Restarting RP switchover behavior:
4.1/ mark所有FIB里面的prefix as Stale；这个时候BGP table是空的，和NSR最大的
不同
4.2/ 重新estalish peering, 因为对方要等timeout (如果对方也timeout，then set
restartbit)
4.... 阅读全帖 |
|
s******v
发帖数: 4495 | 5 1) BGP GR/NSF主要目的：1)HA, traff照旧，因为Fwd LC和RP都是独立，RP
switchover的同时Data Fwd不受影响；2)减少CP traf，因为BGP session reset，
withdraw会波及到所有的BGP Peers，Up之后又是新的一轮update；
2) Peering的时候BGP announce GR capability + AF/SAF，如果没有AF，Router只是
GR Awareness，但是不能perform GR，就是single RP router/或者是GR helper;
3) GR很重要的一点是可以send EOR packet; 表明所有的update完毕；
4) Restarting RP switchover behavior:
4.1/ mark所有FIB里面的prefix as Stale；这个时候BGP table是空的，和NSR最大的
不同
4.2/ 重新estalish peering, 因为对方要等timeout (如果对方也timeout，then set
restartbit)
4.... 阅读全帖 |
|
u*****e
发帖数: 47 | 6 最近刚开始接触juniper的产品，路由器，还真是跟cisco 有很多的不一样啊。搞得头
疼啊。。目前手上的资料也就只有juniper bgp configuration guide...着实压力不小
。经理又催着给配置文件（ibgp & ebgp，我们的网有点小复杂。。。）
1：
公司购买了/22的超网，但是在配置时，在路由器上还是划分成/25的小网段。现在要配
置BGP， 公司要求要把/22和/25都宣告出来。请问这个/22该怎么宣告呢？ 有点没想明
白该怎么宣告/22网段。毕竟不在机器上啊。。。
2：
在juniper上配BGP，关于宣告网段，是不是只能用bgp routing policy 去做。比如
inject OSPF ， 把直连导入BGP？对于ibgp 和ebgp, 这个导入的命令得做两次，对吧
？（记得cisco，只要宣告一次，ibgp和ebgp都可以用。） |
|
c*****i
发帖数: 631 | 7 不知道你说的bgp add-path和我理解的是不是一样。比如一个ce dual-home到2个PE，
PE1和PE2.正常情况下，PE1-CE是best path。PE1的bgp会ignore PE2 advise的PE2-CE
prefix.如果有bgp add-path，这时候PE1的bgp会把PE2-CE做为到CE的backup path
install进去，直接program在CEF里面。这样当PE1-CE的link down的时候，
convergance会快很多。 |
|
t*******r
发帖数: 3271 | 8 //上一次的
Summary:
Per RFC 4271, Junos will tear down a BGP session upon receiving a malformed
UPDATE. The issue is that Junos may recognize optional, transitive
attributes that are not yet recognized by other vendors' routers. In this
case, non-Junos routers which don't recognize the attribute just pass the
UPDATE through with the Partial bit ON. Junos, however, would recognize the
path attribute and perform validation. If the packet has errors, a Junos
router will send a NOTIFICATION (Error code ... 阅读全帖 |
|
s*****g
发帖数: 1055 | 9 A basic BGP feature "bgp allow-as in" will allow prefixes with its own AS in
AS-PATH into local BGP/routing table, by-pass BGP's loop-avoidance
algorithm, so to speak. Is this what you are asking? or if you are not multi
-homing, you just import default route from your local ISP.
Unless you are tier-1 ISP, you most probably don't need your own transport.
For Netflix's CDN, read their "open-connect" white paper, nothing fancy at
all.
datacenters
realized |
|
u*****e
发帖数: 47 | 10 深夜上来向大家再请教一个问题：
我有一个路由器，上面两个ISP线路，也就是两个BGP sessions. 我的目的是在其中一
根线出问题，比如down了，我的数据流能以最短的时间，切换到另外一根线上。丢包能
越少越好。
起初我配置了两根线，两个BGP，就是希望，在一根线出问题时，另外一根线可以take
over所有的数据。实际上也是这样，但是我发现了一个问题：这个切换时间好像比较长
，不能满足我们的要求。
一下是我的分析，请大家给点意见：
当本地路由器60秒内没有收到keepalive 包（比如对方的路由器down了），他就要再等
一个holdertimer 180秒的时间，然后，BGP session 就被认为彻底的down了，TCP链接
也被关闭了。这个时候，路由器才会删除原来的路由，然后接受从另外一根线来的路由
。（两根线都是通告全网路由。）我感觉这个过程应该是对的把。可是从链路down开始
，到本地路由器完成路由表的更新，好像至少240秒。。。这个是不是太长了？
我现在想到的方法是在确认uplink down时，直接进行 BGP 软清。 但是还没有做过测
试，不知道，这样会不会... 阅读全帖 |
|
s*****g
发帖数: 1055 | 11 That will be taken care of by BGP protocol itself.
ISPs are very conservative in terms of BGP configuration, for them stability
is more important than flexibility or customer preferences (for example,
Level3 does not even want to turn on ORF capability), your best bet of
faster fail over is to shorten BGP hold timer if you are peering with
loopbacks (if you are peering with physical interface IP, BGP fast external
failover functionality will automatically kick in without waiting for hold
timer t... 阅读全帖 |
|
t*******r
发帖数: 3271 | 12 Please ask Eric rosen, why virtual router is beat by RFC 2547 back to 10
years ago, control plane signaling aggregation for sure better than
virtualizaing for each customer instance. if multicast bgp can just use PIM
without BGP, can we consider further to remove BGP for unicast as well? i.e
run ospf to cpe, extend ospf to cross the core. |
|
s*****g
发帖数: 1055 | 13 You are configuring 6PE? in that case under ipv6 address family you should
redistribute ripng not rip, right? I doubt IOS would allow you to
redistribute rip under ipv6 unicast address family.
Does 10.2.1.3 have 6PE configured? did the two neighbors negotiate afi/safi 2
/1 and 2/4? You mentioned the PE-CE is IPv6, but I don't see IPv6 BGP
neighbor under ipv6 unicast address family. I would turn on bgp debug and
then clear the whole BGP neighbor. |
|
z**r
发帖数: 17771 | 14 你在router bgp 1下面加上一条no bgp default ipv4-unicast看看。你这个是最基本
的6PEconfiguration，通常在mixed unicast/multicast or ipv4/ipv6等情况下，建议
no bgp default ipv4-unicast，这样你可以清楚的控制每一个协议。不过别忘了加了
这条命令，你需要在address-family ipv4里面activate一下你的ipv4 neighbors |
|
x*********n
发帖数: 28013 | 15 小弟现在看BGP看的有点苦恼，
有些问题detail不是很清楚，看到一半总会出来点redistribution啦，这个routing
table啦，那个BGP table啦，越弄越糊涂了。
是不是要先看一遍IGP，至少把ospf搞明白了，在看BGP会效率高一点？ |
|
m**w
发帖数: 100 | 16 昨天看到你的另一个帖子的一些pick，最后看中BGP，在$1.2买了3000股，没想到今天
就大涨开始启动了。真是太感想楼主了！从来没发过帖子，第一次发贴，就是想表达一
下对楼主的感谢之情！冒昧问一下，楼主觉得BGP能上什么价位？$1.7左右能抛吗？谢
谢！ |
|
m**w
发帖数: 100 | 17 新手，买了些BGP（要被鄙视了）。BGP今天申请破产，不能交易了，怎么办？接下来是
要场外交易吗？还是等破产重组后重新挂牌？谢谢。 |
|
j****r
发帖数: 30 | 18 This is not the only bgp router in our network, we have other routers with
bgp sessions to different ISPs.
We have made decision last week to move the two Ts together and use ppp
multilink. I was just try to find out a way to avoid this time-consuming
change if possible.
Thanks anyway to everybody for the ideas.
approaches
)
are
makes |
|
j****r
发帖数: 30 | 19 This is not the only bgp router in our network, we have other routers with
bgp sessions to different ISPs.
We have made decision last week to move the two Ts together and use ppp
multilink. I was just try to find out a way to avoid this time-consuming
change if possible.
Thanks anyway to everybody for the ideas.
approaches
)
are
makes |
|
d****i
发帖数: 1038 | 20 cisco IOS 长期不支持 vpls using bgp as signaling， 这里面当然有与juniper别苗
头的意思，
尤其是 Lucas Martini很不喜欢bgp vpls， 但是比较这两者，从技术上说，各有什么
优劣呢？ |
|
s*****g
发帖数: 1055 | 21 1) BGP is doing too much already
2) LDP signaling for VPLS is a natural evolution from point-to-point L2
service signaling, why introduce an totally different protocol for
multipoint?
3) LDP is probably un-avoidable in the network to provide MPLS
transportation, but is it always true that a VPLS PE router also always run
BGP? I think not. |
|
d****i
发帖数: 1038 | 22 客户为什么会specially 需要bgp vpls 呢？从大家的讨论看，那个RR feature可能是
一个重要原因吧。不过也可能是vendor忽悠的结果。 客户也未必真需要，但是你有他
没有，客户自然就要两者都有的了，多一种选择么。
IOS 因为不支持bgp vpls，最近很多招标直接出局了。 |
|
d****i
发帖数: 1038 | 23 I think ldp-vpls's answer to the scale issue is H-VPLS. And H-VPLS has
advantage in mac-learning and withdraw compared to bgp-vpls. the RR solution
in bgp-vpls still has to flood mac withdraw to every pe, and each pe still
will keep the macs of every other PE. |
|
s*****g
发帖数: 1055 | 24 post your bgp configuration, "sh ip tcp connections", and reset the BGP
connection? |
|
s******v
发帖数: 4495 | 25 这个很难讲，不好比，最少我没有听说或有人这样比过。
how is the OSPF scale? # of prefix, # of peers?
BGP，像7200/NPEG1，或者7600/sup720, ASR1000/RP1, 500K pfx，300+ peers，没什
么问题，如果hardclear或者是interface flap，convergence大概是<10min, 如果没有
flap，那cpu就是<10%。因为bgp hello is very light.
OSPF，我都忘了，有periodic updates with all pfx？ |
|
z**r
发帖数: 17771 | 26 是不好比啊，所以问问你，看你们有没有这方面的testing results。
现在的OSPF有大约500个neighbor，总共30k routes，大约200k LSA，主要是type 3.如
果光这点东西，没有问题，问题是这个router还有很多其他的东西，比如ISIS, BFD,
Mcast, IPv6, BGP等等，这样一搞，就不行了。
OSPF在这里肯定是不scalable的，所以想转一些到BGP，知道会省一些CPU，但是从来没
有人测试过到底能省多少。看看能不能有个大概的数字 |
|
s******v
发帖数: 4495 | 27 is that ios? you can try with "show proc cpu sorted | inc ospf|bgp". not
sure the platform, but general speaking, bgp with that scale is about 10-20%
cpu max on a NPEG1/7200. in middle of conv., that will be up to 100%:-) you
know that. |
|
x*********n
发帖数: 28013 | 28 用 loopback 做router ID,如果AS都是65011，那不是ibgp么？
这个ebgp-multihop 20是啥意思呢？
router bgp 65011
no synchronization
bgp log-neighbor-changes
network 172.16.220.0 mask 255.255.255.0
neighbor 172.16.20.1 remote-as 65011
neighbor 172.16.20.1 ebgp-multihop 20
neighbor 172.16.20.1 update-source Loopback0
neighbor 172.16.20.3 remote-as 65011
neighbor 172.16.20.3 ebgp-multihop 20
neighbor 172.16.20.3 update-source Loopback0
neighbor 172.16.20.4 remote-as 65011
neighbor 172.16.20.4 ebgp-multihop 20
neighbor 172.16... 阅读全帖 |
|
x*********n
发帖数: 28013 | 29 BGP or EBGP is the only protocol works with different AS.
so when you got BGP, you can advertise your internal network to public, most
time, when you are running ospf, it would be much easier for your ISP to
know which network we should advertise out.
on the other side, ISP may have some filter by as-path list or community-
list to filter out by accepting routes from customer.
the traffic goes different way is very normal, simply the ISP PE got
different ways to deal with traffic.
the edge route... 阅读全帖 |
|
x*********n
发帖数: 28013 | 30 eBGP needs to directly connected, iBGP doesn't
eBGP 不directly connected也能peer，3种方式，一种是常见的emulti-hop，一种是
disconnected，一种是TTL-max啥的，总之都是改TTL。
BGP是over TCP的，你想啊，这都是在layer 4了，底层是要有IGP running的。
synchronation都是要和IGP match才能做BGP的。
你可以把interview题目发上来，大家帮你看看，弄清楚了，下次就不会错了。 |
|
n**********l
发帖数: 271 | 31 origin is set by the origin AS, usually meaningless for traffic engineering.
Different vendors use origin differently.
A common practice is to rewrite origin in all received routes.
core1.fmt1.he.net> show ip bgp routes detail 8.8.8.8
Number of BGP Routes matching display condition : 15
S:SUPPRESSED F:FILTERED s:STALE
1 Prefix: 8.8.8.0/24, Status: BI, Age: 9d1h58m39s
NEXT_HOP: 184.105.224.254, Metric: 15, Learned from Peer: 216.218.
252.165 (6939)
LOCAL_PREF: 10... 阅读全帖 |
|
x*********n
发帖数: 28013 | 32 BGP都是unicast的吗？不好意思问的傻了。好像是从来没见过BGP别的花样。 |
|
x*********n
发帖数: 28013 | 33 哦。。我在理解理解。 脑子有点混乱。
SP 3种vpn， layer 2vpn，layer 3 vpn， vpls，
常用的mpls vpn算是layer2吗？，底层跑IGP，take care ipv4，上面跑mp-BGP，take
care vpnv4，
你说的multicast是说非vpn应用下的吗？multicast不是有其他的protocol吗？BGP
multicast干嘛啊？
有点不太理解。。 |
|
u*****e
发帖数: 47 | 34 Hi buyup,
再次感谢你的回复。我下午网上查了点资料，关于你说的BFD, 现在有几个问题还请你
帮忙解释一下：
一旦我们启用了bfd以后，比如我设置那个bfd liveness detection 是一秒，那么一旦
我本地路由器没有收到回复，是不是路由起马上就把当前bgp session 给kill, 转到另
外一个bgp 线上了？ 这个过程是怎么运作的？在网上没有看到说的很清楚的。。
你提到两个方法，第一种是10秒级的，就是修改timer，我感觉这个不是很适合我们的
video service. 估计这个bfd 可能更适合我们的需求。
另外，又看到大家提出，ip FRR： 如果我们使用bfd，我们是否仍然需要这个呢？我们
的所有设备都是juniper 的，我看了，juniper 好像有个类似的协议：Host fast
reroute (HFRR)。 你熟悉这个吗？
谢谢！
check |
|
b***p
发帖数: 700 | 35 from your prev post, you have ONE router facing SP network. If the BFD
detects other side is down and notify the BGP, this bgp will withdraw all
prefix and re-advertise the ones from backup SP. I am not sure if this is
what you are asking.
Above it is the fast failure detection between your network and SP.
Fulcrum's idea IP FRR is to fast-reroute your internal networks, if one node
/link is down on the path, the router can switch to pre-calculated path
during the IGP working on the new path. But... 阅读全帖 |
|
u*****e
发帖数: 47 | 36 先感谢大家的热心回复。我简单的 说一下我的网络结构吧。
(router1)-------(router2)
每个router都连有两个isp，都做了bgp， 两个router之间我还配置了ibgp. 所有的
bgp都接受全网路由。 这样做的目的就是为了在其中一根线断了之后，数据流可以尽快
的切换到其他线上去（不管是去自己路由器的另外一根线，或者是另外一台路由器。不
过我估计他会优先选择本机的另外一根线把。。。。）。
现在基本可以确定，bfd会是我的一个必要选择。但是请问，基于我现在的结构，ip
frr，有需要吗？ |
|
u*****e
发帖数: 47 | 37 最近都在讨论这个BFD如何切换的问题。我还想到一个问题：假设BFD成功的发现链路
failure,然后BGP也成功切换了。那么当原来那根线路恢复了，现有bgp table 和
routing table会发现什么变化？ （这个有点类似于vrrp的一个问题，当原来的
primary node 恢复了以后，会不会发生抢占的问题。。。）
谢谢 |
|
a*****s
发帖数: 49 | 38 BGP has a well-know mandatory attribute named AS-PATH.
BGP uses this attribute to detect and prevent loop.
Refer to rfc1771 section 5.1.2 |
|
o*****8
发帖数: 83 | 39 〔美国热股〕William Ackman将资助Borders对Barnes & Noble的收购
路透纽约12月6日电---根据一份提交给监管机构的文件,对冲基金经理William Ackman
已准备好资助Borders(BGP.N: 行情)对竞争对手Barnes & Noble(BKS.N: 行情)每股16
美元的收购.
上涨空间很大。 |
|
o*****8
发帖数: 83 | 40 BGP今天要开始爆发了，盘前已经1.57，昨天有人跟了吗？ |
|
|
|
m**w
发帖数: 100 | 43 教训深刻啊。现在在scottrade里面，BGP变成BGPIQ了。但是无法交易。是不是意味着
现在要场外交易了？怎么弄啊？ |
|
g********4
发帖数: 4959 | 44 忘了连打印机。
发信人: bcdoudou (doudou), 信区: Stock
标 题: Re: 买了BGP，公司破产，怎么办？
发信站: BBS 未名空间站 (Wed Feb 16 09:56:15 2011, 美东)
通常公司破产了，你可以如下操作：
1.打开broker的网站，点击该股票代号
2.按住键盘ctr和p
3.打印好后将其贴在墙上 |
|
L*****3
发帖数: 922 | 45 清不清0一切都要看他家的重组和重新融资计划，当然现在绝大多数破产保护公司都
dump老shareholder.
但是，即使如此，你的股票清0还早的很，两大车当年快速出破产保护也得几个月，一
般都得1-3年，甚至5年，在此之前，哪怕公司宣布抛弃原来的shareholder，股价都不
会变0。
所以不要惊慌，破产股几天后会交易，然后不是没有机会，专门有庄炒这个，bgp不同
车厂，可能不会那么疯狂，但机会还是有，看看当年的VSTNQ，打到2分再被炒到近2块
。 |
|
f**k
发帖数: 906 | 46 ☆─────────────────────────────────────☆
zher (民工.有劲) 于 (Tue Oct 5 00:05:21 2004) 提到:
工作有一定压力，但是公司前景看好。地点在加州，如果你感兴趣，愿意一起奋斗3、5年
请把resume发到z*********[email protected]
☆─────────────────────────────────────☆
scurf (头皮屑) 于 (Tue Oct 5 01:41:12 2004) 提到:
民工当老板拉?
☆─────────────────────────────────────☆
tzq (egg) 于 (Tue Oct 5 03:08:30 2004) 提到:
啥是bgp阿？只能现学了，55555
☆─────────────────────────────────────☆
zher (民工.有劲) 于 (Tue Oct 5 20:10:38 2004) 提到:
还是打工啊，帮公司找人啊，厚厚
☆────────────────────── |
|
l******e
发帖数: 27 | 47 Routers only run protocols at and below IP. Why routers can establish TCP
connections to exchange BGP messages? Thanks. |
|
c*a
发帖数: 806 | 48 ldp, bgp, msdp
any other protocols using tcp? |
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w*****r
发帖数: 89 | 49 even a theoreatical router, BGP, a level 7 protocol, is there, hehe
unless you are really really paranoid about that definition of "router"
hehe |
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j****r
发帖数: 30 | 50 All Cisco experts,
We are running bgp on many routers for Internet load balance. We have two T1
circuits from one ISP, let's focus on these two T1 circuits.
On our side, the two Ts terminate on the same router, on ISP side, they
terminate on different routers. Most of time, one circuit got 100% saturated,
the other one has only 20% usage.
Is there any way easy to adjust the load between the circuits? we only care
about the inbound traffic. |
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