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  • 1.  HPE 5130 dropping pings

    Posted Oct 21, 2019 05:14 AM

    I have a workstation and a bunch of embedded real-time systems in a private network. (I would attach an image, but I guess that is not allowed for new users.) The number of embedded devices increased, so I replaced our HP Procurve 2524 switch with a new HPE 5130-48G-PoE+-4SFP+. The workstation has IP address 192.168.1.1, and the embedded devices span a continuous range of IP addresses in the 192.168.1.0 subnet. Bridge configuration is fine for this purpose (except that I would like to be able to remotely manage the switch from the workstation), so I started testing with the switch factory settings.

    Pinging the embedded devices from the workstation with increasing packet size caused lost packets already at little over 8 kB. I enabled jumbo frames and burst mode, but these didn't have any effect. Does anyone have any ideas what might be causing this? I also seem to get ten to hundred times longer latencies in the private network than I do with the same workstation in a public network with an identical switch.

    Another question: After the tests, I enabled remote management. I can now use the management GUI, but I would rather use CLI. However, I get "Connection to 192.168.1.2 closed by remote host" as soon as SSH accepts the password. Any hints on what might still be missing from the configuration?

     



  • 2.  RE: HPE 5130 dropping pings

    Posted Oct 25, 2019 06:56 AM

    Hi,

    Are the following commands added on to the device? I've had issues with ping/traceroutes before an using these helped.

     

    ip unreachables enable
    ip ttl-expires enable



  • 3.  RE: HPE 5130 dropping pings

    Posted Dec 04, 2019 02:30 AM

    Hi,

    I'll try to address some of your points.

    Pinging the embedded devices from the workstation with increasing packet size caused lost packets already at little over 8 kB.

    Was this also an issue with the Procurve-switch, or is this a newly arisen problem (when you deployed the 5130)? Embedded devices are usualy small with close to very little CPU. Sending large frames to the CPU might not just be a good idea.

    I also seem to get ten to hundred times longer latencies in the private network than I do with the same workstation in a public network with an identical switch.

    What do mean here? Public Network vs private network. Do you mean on a network using public addressing (i.e not RFC 1918 addresses?)  Anyway. Increasing ping times when pinging "through" the switch is not related to the switch. (Switch just forwards packets)

    Another question: After the tests, I enabled remote management. I can now use the management GUI, but I would rather use CLI. However, I get "Connection to 192.168.1.2 closed by remote host" as soon as SSH accepts the password. Any hints on what might still be missing from the configuration?

    You need to do a few things before ssh works.

     

    public-key local create rsa
line vty 0 63 
 authentication-mode scheme 
 protocol inbound ssh
 quit
domain <name-of-your-domain>
 <define-your-aaa-methods> # tacacs+ / radius / local
 quit
default domain <name-of-your-domain> enable

     

    Also, if your method is local, you want to create a local user for that purpose. 

     

    local-user <local-user-name> class manage
 password hash <password-hash>
 service-type ssh
 authorization-attribute user-role network-admin #user can do anything
 quit

     

     

    Regards



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