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EX2200 limit SSH access

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  • 1.  EX2200 limit SSH access

    Posted 01-11-2018 05:10

    Hi all,

     

    I recently configured a few EX2200 switches. I want to limit the management access(SSH) to a few sources.

    On my SRX I have a L3 wan interface, with a few VLANs.

     

    From a Juniper SRX point of view, I would limit the SSH access via something like:

    set security zones security-zone management interfaces vlan.27 host-inbound-traffic system-services ssh

     

    There is no such option on the EX2200 as there are no security zones... At this moment I have applied a filter to all individual L3 interfaces, but I am guessing this can be done more efficient. 

     

    Any thoughts?

     

    Piet

     



  • 2.  RE: EX2200 limit SSH access

     
    Posted 01-13-2018 05:15

    On any Junos device besides the SRX we use firewall filters for this purpose.  See chapter 5 page 59 and following in the free Day One: Finishing Junos Deploys book.

     

    https://forums.juniper.net/t5/Day-One-Books/Day-One-Finishing-Junos-Deployments/ba-p/272763

     

    These are packet access control filters that get applied to the interface on the protected device to restrict access per protocol.  Similar to a policy but these have no session table or awareness just a straight packet filter.

     



  • 3.  RE: EX2200 limit SSH access

    Posted 01-16-2018 08:53

    Hi Steve/Karan,

     

    Thank you for your reply,

     

    I understand that I must use firewall filters and apply it to the interfaces. So basically there is no other option then apply filter(s) to all interfaces?

     

    The reason why I am asking this is because I have a loopback interface on which a firewall filter is applied, so that I can only reach/SSH the switch(loopback interface) from my management network. However, SSH(and such) is still open to the box on my WAN/ LAN interfaces.

     

    That means I need to apply filters to those interfaces also, which seems a bit off when you compare it to ,for example, a SRX where you allow it with something like:

    "security zones security-zone MANAGEMENT interfaces vlan.20 host-inbound-traffic system-services ssh"

     

    But from what I understand, there is no such option and the only possibility is with multiple firewall filters/ filters for to-the-box traffic per interface.

     

    Regards,

     

    Piet



  • 4.  RE: EX2200 limit SSH access
    Best Answer

     
    Posted 01-16-2018 09:51

    Hi Piet,

     

    Usually, its the loopback address that's the most routed & advertised IP address on the router/switch (towards its known peers) thus the filter is applied commonly onto router/switch loopback.  If your uplinks/downlinks (such as accessLink/wanLink) is IP routable from far remote end outside your network, then yes, you may wanna apply filters on them but again that depends from setup to setup, a firewall node should block such unauthorized access.

     

    Security zone configuration set is specfic to SRX/vSRX Series and unfortunately doesn't apply to our subjected node, EX2200.

     

     

     



  • 5.  RE: EX2200 limit SSH access

     
    Posted 01-13-2018 05:26

    as rightly pointed by spuluka, Here are couple of firewall filter sample configuration:

     

    [EX/QFX] How to provide SSH access to specific IP addresses and restrict SSH access to all other IP addresses:

    https://kb.juniper.net/InfoCenter/index?page=content&id=KB24764

     

    [EX] How to limit SSH login for management to a range of IP address:

    https://kb.juniper.net/InfoCenter/index?page=content&id=KB19171

     

    /Karan Dhanak

    #Mark my solution as accepted if it helped, Kudos are appreciated as well.