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  • 1.  Default VLAN not accessible EX2300-C

    Posted 04-24-2023 10:35
      |   view attached

    Hi, I am new to Juniper, and learning JunOS now,
    Here is the situation:
    I created vlan1(10.216.0.x) vlan2(1.x) vlan3(2.x), vlan 2 and 3 are fine but vlan 1 not accessible. trunk is connected to ge-0/1/1, irb.0 is vlan 1 L3-interface
    irb.0 can get ip address from dhcp but cannot ping through, the ge interfaces attached to vlan 1 are also not accessible. interfaces attached to vlan 2,3 are fine

    trunk other side is CISCO switch, allow 1-4094 tagged vlan
    attached my config file. 



    {master:0}
    root> ping 10.216.0.1
    PING 10.216.0.1 (10.216.0.1): 56 data bytes
    ^C
    --- 10.216.0.1 ping statistics ---
    2 packets transmitted, 0 packets received, 100% packet loss

    {master:0}
    root> ping 10.216.1.1
    PING 10.216.1.1 (10.216.1.1): 56 data bytes
    64 bytes from 10.216.1.1: icmp_seq=0 ttl=255 time=100.456 ms
    64 bytes from 10.216.1.1: icmp_seq=1 ttl=255 time=8.644 ms
    ^C
    --- 10.216.1.1 ping statistics ---
    2 packets transmitted, 2 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 8.644/54.550/100.456/45.906 ms

    {master:0}
    root> ping 10.216.2.1
    PING 10.216.2.1 (10.216.2.1): 56 data bytes
    64 bytes from 10.216.2.1: icmp_seq=0 ttl=255 time=13.175 ms
    64 bytes from 10.216.2.1: icmp_seq=1 ttl=255 time=8.337 ms
    64 bytes from 10.216.2.1: icmp_seq=2 ttl=255 time=5.368 ms
    ^C
    --- 10.216.2.1 ping statistics ---
    3 packets transmitted, 3 packets received, 0% packet loss
    round-trip min/avg/max/stddev = 5.368/8.960/13.175/3.217 ms

    {master:0}

    root> show route

    inet.0: 7 destinations, 9 routes (7 active, 0 holddown, 0 hidden)
    Limit/Threshold: 32768/32768 destinations
    + = Active Route, - = Last Active, * = Both

    0.0.0.0/0          *[Static/5] 02:42:19
                        >  to 10.216.1.251 via irb.2
                        [Access-internal/12] 00:27:11, metric 0
                        >  to 10.216.0.1 via irb.0
                        [Access-internal/12] 00:19:02, metric 0
                        >  to 10.216.2.252 via irb.3
    10.216.0.0/24      *[Direct/0] 00:27:11
                        >  via irb.0
    10.216.0.123/32    *[Local/0] 00:27:11
                           Local via irb.0
    10.216.1.0/24      *[Direct/0] 02:42:19
                        >  via irb.2
    10.216.1.210/32    *[Local/0] 02:42:19
                           Local via irb.2
    10.216.2.0/24      *[Direct/0] 00:19:02
                        >  via irb.3
    10.216.2.38/32     *[Local/0] 00:19:02
                           Local via irb.3

    inet6.0: 3 destinations, 3 routes (3 active, 0 holddown, 0 hidden)
    Limit/Threshold: 20480/20480 destinations
    + = Active Route, - = Last Active, * = Both

    fe80::ee94:d500:75:46a4/128
                       *[Local/0] 02:42:09
                           Local via irb.0
    fe80::ee94:d5ff:fe75:46a5/128
                       *[Local/0] 02:42:44
                           Reject
    ff02::2/128        *[INET6/0] 02:42:45
                           MultiRecv

    {master:0}



    ------------------------------
    ROGET LUO
    ------------------------------

    Attachment(s)

    txt
    conf.txt   6 KB 1 version


  • 2.  RE: Default VLAN not accessible EX2300-C

    This message was posted by a user wishing to remain anonymous
    Posted 04-25-2023 16:46
    This message was posted by a user wishing to remain anonymous

    As VLAN 1 is the default native VLAN, it is used for untagged traffic. If you need to pass frames tagged VLAN 1, you will not be able to, by default. The solution is to change the default VLAN to another value. Once this is done, VLAN 1 can be passed across the trunk just the same as any other VLAN.




  • 3.  RE: Default VLAN not accessible EX2300-C

    Posted 04-26-2023 10:31

    Thanks for your reply. I deleted default VLAN and still not able to ping through. It's werid that client in VLAN 1 can obtain IP address but cannot ping
    I wonder this is caused by CISCO side. I attach the trunk link to my laptop ethernet and change adaptor VLANID tag to 1 and cannot obtain IP address, change VLAN IDtag to 2 works. I have a linux Server connec to CISCO trunk line works fine

    Maybe I need help from CISCO . Thanks again!



    ------------------------------
    ROGET LUO
    ------------------------------



  • 4.  RE: Default VLAN not accessible EX2300-C

    Posted 04-27-2023 05:38

    > As VLAN 1 is the default native VLAN, it is used for untagged traffic. If you need to pass frames tagged VLAN 1, you will not be able to, by default. The solution is to change the default VLAN to another value. Once this is done, VLAN 1 can be passed across the trunk just the same as any other VLAN.

    This may be true for Cisco it is NOT TRUE for Juniper. Vlan 1 is another vlan just like any other. If you want to have it untagged on a trunk, specify it as such, otherwise it will be tagged (by default).

    The default vlan is something else. It's not equal to vlan 1. All ports not having been assigned a vlan id explicitly will have the "default vlan" assigned (I guess they're using id 0 internally). They will be in the same vlan, but the frames will never be able to leave the switch. This may be issue here.

    Do not use the default vlan. Set all ports in a vlan explicitly (or use a L3/routed port).



    ------------------------------
    Erik Slagter
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