When to use BGP-address family?

I often see BGP configured on a router of the provider (P/PE) like this (he is a true router just anonymizated extract);

router bgp 12345

Remote 1.1.1.1 neighbor - as 12345. iBGP peer

ipv4 address family

Remote 1.1.1.1 neighbor - as 12345. iBGP peer

vpnv4 address family

Remote 1.1.1.1 neighbor - as 12345. iBGP peer

address ipv4 vrf Customer1 family

neighbor 10.0.0.1 remote - as 67890! eBGP peer

  • I understand the CE peering defined under the 'family of addresses ipv4 vrf Customer1' because we put their journey in this VRF
  • I understand that "address-family vpnv4" is used to define peers from iBGP provider to be attached, carrying this customer VRF to another CE
  • Finally, I understand that a provider's router is an iBGP peer so that it is set directly under "router bgp 12345".

What is the need for a 'family of ipv4 addresses' (without the vrf) here or never?

What it does the output as 'normal' neighbor definitions (those who are directly under "router bgp 12345") and nearby definitions vpnv4, do not provide?

Hello

The BGP, as you know, has a capacity of Multiprotocol - in one sitting, it is capable of carrying information about the various routed protocols (IPv4 Unicast, Multicast IPv4, IPv6 Unicast, Multicast IPv6, VPNv4, CLNP), in the jargon of BGP called "address families. With being a true multiprotocol routing protocol BGP, however, you all way to say BGP address what families should be exchanged with a neighbor especially. We are accustomed to the fact that, if we define a neighboring IPv4, we intend to Exchange IPv4 routes with this neighbour - but why is making a rule? Why do assumptions early on the address simply family because the address of the neighbor is from a family special itself?

That's the point behind the controls of the address family . Definition of a neighbor in a particular address family means we want to Exchange routes of specific address with this neighbour family. No no not a neighbor listed under a particular address family means that we do not expect to exchange information of this family of addresses with this neighbour.

Now, ipv4 address family says neighbors with whom we want to Exchange normal IPv4 unicast routes. It's perhaps surprising because to Exchange IPv4 routes with a neighbor, just simply set this neighbour by its address. The fact is that for backward compatibility with older BGP versions that were not Multiprotocol-capable, the BGP attributes implicitly defined all the neighbors to a section of the invisible -ipv4 address family . In other words, as soon as you set a neighbor, it is automatically added to a section of the invisible -ipv4 address family so that you don't have to do it manually.

You can change, however. First of all, if you enter the BGP configuration command bgp upgrade-cli , you will find that the BGP configuration has been converted entirely to the family style address configuration. Outside any family address stanzas, only the nearby base settings are configured as their addresses, as numbers, updated sources. However, all orders by family of remaining addresses will be automatically moved into the stanzas of the address family. The behavior or BGP operations do not change with this new style of configuration, only the format of configuration is changed.

In addition, if you enter the No bgp ipv4 unicast default command configuring BGP, BGP will prevent you from automatically assigning each neighbour newly defined in the section of the ipv4 address family . You then must add each neighbor set to each scheduled automatically - address family it does automatically for you more.

So to wrap - ipv4 address family is in fact a pervasive section in the BGP configuration but for reasons of backward compatibility, it is not visible by default. However, the configuration can be converted into a configuration by address-family-strict, and in fact, I would recommend that for all new deployments.

Please feel welcome to ask for more!

Best regards

Peter

Tags: Cisco Network

Similar Questions

  • How can I make all the emails on a .bcc of distribution list when you use the address book?

    When I send an email to a "list" in my address book I want to warn all the email addresses of the recipients to be visible by all byhaving be the entire list > bcc - how can I do this with Thunderbird?

    Place the list in an address field, click the TO and replace it with BCC.

    If you do not Contact sidebar enabled in the entry window press F9 to turn it on. Select contacts or to the mail list, then use the button Add to the BCC.

  • I had Google as search engine by default, when I used the address bar to search for, but Yahoo has hijacked this function and I can't get default Google.

    Windows Firefox 29.0.01 8.1

    It doesn't seem to be an easy way to reset the default search engine to use in search in the address bar. Am I missing something?

    And also, why can Yahoo turn this function is the default search engine?

    Hi gcraighammond, I just noticed that you had a problem, a right-click. To change the search engine, click with the left button on the icon and a list of search engine options would fall down.

    Yet once, it doesn't until you move the search box back to the toolbar AND to exit to customize the view.

  • When I use the address bar to search for, I redirected to a Web page called 'startpins '. Ive tried several malware removing applications, but none have set it

    It seems there will be no solution on other forums. And I can't trace anything whether it's relevant to this site in my computer

    Hello pan903, you can try to install the addon Search reset , or manually reset the url search engine by typing on: config in the address bar of firefox (confirmed the message information where it appears), seeking the preference named keyword.url and right click and reset it to its default value.

  • How to remove all the old e-mail addresses when you use change as new?

    When you use as new edit on a mail, previous winners are listed in the address field. How to delete these addresses all at once rather than having to delete them one at a time?

    I don't know of anyway to remove them all at once, but there is remove an add-on that places a button next to each address, which is easier to use that repeatedly do select + and + DELETE. You just keep clicking the small X in the address above.

    https://addons.Mozilla.org/en-us/Thunderbird/addon/address-close-button/?src=API

  • How can we change the preference which e-mail address thunderbird uses to send an email when you use the button "write"?

    I currently have two accounts in use on my thunderbird. When sending emails on Mozilla Thunderbird, immediate preference is to send from the first account I added to the program, but most of the time, I only want to send emails on the second account. I often forget to change the e-mail address of the sender to the top of the message window that becomes a gene. I don't know there must be a way to change the preferences around, but for the life of me I can't find it anywhere!

    If you are viewing emails and folders for the account 'A' and choose to write a new message, and then FROM use e-mail address of account 'A'.

    If you were displaying foldres 'B' and email account and choose to write a new message, and then FROM use account address email 'B '.

    If you view e-mails in local folders and choose to write a new message, then FROM using anything that is set as default.

    At the top e-mail account is the default e-mail account.

    You can change which account is set as the default value.

    • 'Tools' > 'account settings '.
    • Select the e-mail account you want to set as default
    • Click on "Actions account."
    • Select: "set as default"
    • Click OK to save the changes.

    The news 'Tools' > 'Account settings' guess you have activated all your toolbars. Otherwise, you can also access the "Account settings" via:

    • '3 bar menu icon' > 'Options' > 'account settings '.

    or

    • Right click on the email account in the left pane of the folder, and then select "settings".

    As you have only two e-mail accounts, it is easy to exchange the default and change the order that they are displayed. If later, you add several email accounts and need to change the order of these accounts, not only to define a default value, you can use this addon:

    Please note that this addon also lets you reorganize the folders.

  • Suddenly, when I search using the address field, I am is more directed directly on the site I look for ex-BBC, as I was before. To place a web page

    When I search using the address field, I am is more directed directly on the site I look for ex-BBC, as I was before.

    Instead Google web page appears with a list of proposals, and I have to click on the link to the BBC it to get on the site.

    Ways you can give me the code to insert in the "topic: config" keyword. URL

    r

    Take a look at this module.

    https://addons.Mozilla.org/en-us/Firefox/addon/keywordurl-hack/

  • I can't connect to my account. He says that I already have a LIVE account when I enter my e-mail address, but when I use the "forgotten password", it says that this account does not exist. WTF?

    I can't connect to my account. He says that I already have a LIVE account when I enter my e-mail address, but when I use the "forgotten password", it says that this account does not exist.  WTF?

    Hello

    For questions related to the application, Windows Live, Windows Live Support professionals/moderators will be best placed to help you. I recommend you to ask your question in the support forum for Windows Live for assistance:

    http://www.windowslivehelp.com/

    Hope the helps of information.

  • How can I increase the size of the address bar? When I use the zoom of the icon of the tool, it only increases the size of the screen below the address bar.

    It is difficult to read the address bar in Explorer.  How can I increase the size of the address bar?  When I use the zoom tools icon it only increased the size of the screen below.

    You talk about the size of the text of the elements of windows.

    But the question was about the SIZE OF the INTERNET EXPLORER ADDRESS BAR SIZE.

    It is very difficult to use the address bar now when it 12-15% of the width of the IE.

    To change the TI: right - click on the bar next to the tabs. the drop - down menu select "show tabs on a separate line.

    That's what concerned, imho.

  • When I use the Client for NFS provided by Windows 7, I'm unable to connect. The "mount \\ip address\share Z:" command fails with the error code "the path not found network".

    Identification of customer's Windows 7 NFS UID GID information

    I am trying to connect to the Windows 7 Client NFS on a server running on a computer (VxWorks) NFS.  I am able to properly connect Client NFS software by a 3rd party on the NFS server.  However, when I use the Client for NFS provided by Windows 7, I am unable to connect.  The \\ip address\share Z: mount"command fails with the error code"the path not found network ".  I can't do a ping of the computer running the NFS server.

    The NFS Client operating system: Windows 7 Ultimate, 64-bit

    Data captured by Wireshark

    MOUNT V1 EXPORT call 3rd party client
    Identification information Flavor: AUTH_UNIX (1)
    Length: 32
    Stamp: 0xc7065970

    Machine name: PC
    UID: 1000
    GID: 1000

    MOUNT V1 EXPORT appeal of the NFS client
    Identification information Flavor: AUTH_NULL (0)
    Length: 0

    It seems that the credentials of NFS Client are not correct.  How can I change the flavor of AUTH_UNIX and the UID and GID to 1000?

    Hello VDAEMP,

    As Eddie and Sudarshan has said, the Microsoft Answers community focuses on issues and problems related to the consumer environment. Please join the public IT pro TechNet forums below:
    TechNet - Windows Server
     
    Thank you

  • Firefox 14.0.1 open twice when I use a link to my email address

    When I open Firefox using a link in my mail it opens twice. When I use the normal way "Programs/Mozilla Firefox" or the button on my Firefox desktop opens normally.

    It worked fine, thanks!

  • Mail has stopped allowing me to use Group addresses

    I'm under El Cap 10.11.6.

    Mail left allowing me to use Group addresses. I tried manually, type the group name in the address bar, add the group by using the + function and click and drag.

    When I use the + function, the group is displayed but cannot be selected.

    What is the solution?

    Plot thickens: when I manually add recipients to the BCC line, the email will send but is never received by anyone on any address line.

    I sent from iPad and a Mac, same result. question about iCloud?

  • Could not find ' subject: accidents using the address bar

    My question is with Firefox (35.0.1) constantly crashing, I try to find my submitted incident reports but could not find ' subject: accidents using the address as directed by Mozilla bar. I type "subject: accidents and end up with 'the address is not valid'." My browser crashed between 25 to 30 times in the last 6 days, I presented reports every time and 6 times, I also introduced my address to receive a response, none was forthcoming.
    Home PC is used by a few of us, while the children use their own laptop computer, to save time logging in and out, each of us using another browser. Nobody in our family has problems with IE or Chrome on the PC at home, nor children. The only person to have problems is the poor SAP who drew the short straw - me.

    I can a fair bit of advice? During my research, these constant crashes, I see that many, many others have had the same problem and for quite a few years apparently. Should I just accept that this is part of the use of Firefox and don't forget to take some Valium drops in my tea before logon? or perhaps the healthier choice, find a.n.other browser and move everything out there?
    I wonder Auto Add info and willingness, but understand that I do not use the Firefox browser to do this now because he planted just - seriously.

    Hello type about: crashes without an empty space (on: crashes)

    Thank you

  • I get a file (pixel.cgi) who wants to download when I use certain sites (Groupon / Thomas Cook).

    I get a file (pixel.cgi) who wants to download when I use certain sites (Groupon / Thomas Cook). I scanned my mac for the virus, but none can be found.

    The page has at least 3 forms invisible that automatically submit to securepaths. com which is probably some sort of tracking site. The site sends answers normally capable of managing internal Firefox, so I don't know why you're getting invited to record in the form of a download.

    The standard approach to download actions wrong is to be wary of corruption of the settings file that stores these settings. You can rename the file and Firefox to regenerate to see if that solved the problem. (You will need to review the Applications section of the Preferences dialog box to reselect the default preferences, such as your favorite email client and the PDF Viewer).

    Here's how:

    Open the settings folder (AKA Firefox profile) current Firefox help

    • button "3-bar" menu > "?" button > troubleshooting information
    • (menu bar) Help > troubleshooting information
    • type or paste everything: in the address bar and press enter/return

    In the first table in the page, click the "Show in Finder" button (in Windows: "Show the file")

    Leave this window open, switch back to Firefox and output, either:

    • "3-bar" menu button > button "power".
    • (menu bar) File > exit/Quit

    Pause while Firefox finishing his cleaning, then rename the mimeTypes.rdf to something like mimeTypes.old

    Launch Firefox back up again. Any improvement in the research Manager pixel.cgibar?

    In case they are of some interest, I have attached the screenshots showing:

    (1) the web console (command + Alt + k) - showing that the request to this site is a PUBLICATION, which generally indicates a sending a form or submission script

    (2) source of the generated page (select all, right click, view selection source, find pixel.cgi, select all)

    (3) the network tab of the web console, indicating the nature of the data being sent back to the site after the POST

  • How can I stop Firefox from sinking my IP when I use the proxy settings?

    So basically I use settings from manual proxy on Firefox from time to time to be more anonymous. These proxies are normally rather slow (but hey, it's the price for you to pay for anonymity). Sometimes I'll see a sudden leap of speed. I suspected that the proxy may not work for some reason any. So, I use a website that tells you that your IP address is to see if the proxy settings are really working. Of course when I update the site it gives me my real IP. I have check the proxy settings and it turns out that the browser was restored to use the proxy settings of the system (for some reason that is the default instead of no proxy). This happens randomly and why not apparently when I use the Manual proxy settings and it flees my IP every time that happens (and I never know when it does, unless I am very attentive). Is it possible to prevent him from returning to the system without no reason proxy settings? BTW, I tested the proxy in question after what is happening so it still works which preclude the possibility of the proxy does not (even if that were the case, I'd rather my IP don't Connect at all that the leak). So yes, any help in getting it to stop doing that would be nice.

    Hi internetman, in your system more than details it shows as active. It may or may not be something, but try to disable in case it makes a difference.

Maybe you are looking for

  • Cannot search all my notes with iOS 10

    Since the upgrade to iOS 10 I was unable to search my old notes, it seems that new research notes.  Has anyone else had the same problem? I rebooted a couple of times to see if that helps, but it doesn't.

  • Equium M50-164: not blocking down

    I have an M50-164 and after I am on the web for a few hours I try to shut down the laptop (for example START > TURN OFF COMPUTER > SHUT DOWN) It won't work, that after that I tried 3 times using the same process as above then it will work, or sometim

  • Voice vlan - SG200-50

    Hello I m a fan of IOS CLI. Its the first tiem I have to configure a switch of SB. Sound very confused, I want to setup an id of the vlan 200 voice. but I have the gift of seeing this value changes when I try to apply the smartport macro interface. I

  • PDM 3.0 (1) problem

    Hello I have a PIX 535 with: Cisco PIX Firewall Version 6.3 (1) Cisco PIX Device Manager Version 3.0 (1) The problem is that when I opened the PDM, I see nothing that the background (windows PDM with Menu). Strange things is that I get the message th

  • Cannot search screen start tapping just

    I don't know when it has stopped working, but I can look for is more of the screen of Windows 8 start by just typing.  I have to go out to search for charms. And when I go out the charm and the charm of search it gives me the ability to search "files