Old switches (B2, C2, C3 - Switch Management stop)

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I understand these switches are out of warranty and EoL and EoS, but maybe someone can give us some guidance?

A client of ours has a couple of the B2, C2, C3 switches deployed on the management VLAN for the Cape Town Data Centre.

For some reason the switch stops responding on its management interface.  No ping, snmp etc. to the Managment IP or from the Management IP to any other IP.

When one connects via console cable to the switch you are able to ping the configured management IP locally, but nothing else on the same subnet.

One is even able to configure a laptop for the same subnet and plug it into another port on the switch and ping other IPs which comes in via an uplink cable.

From the core switch if I do a show neighbor, I can see the problematic switch:

sw-ctdc-core1(su)->sh neighbors ge.8.6

TYPES:   LL = LLDP         Ct = CtronDp        Ci = CiscoDp


Port      Device ID         Port ID   Ty Network Address


ge.8.6    00-1f-45-76-d5-68 ge.1.44   LL

ge.8.6    00-1f-45-76-d5-68 ge.1.44   Ct

ge.8.6    001f4576d568      ge.1.44   Ci


But from the problematic swich, I cannot see the core as a neighbor IP (although the correct port on the core is shown)

sw-ctdc-3rd-1(su)->show neighbors  ge.1.44

  Port       Device ID            Port ID           Type       Network Address


ge.1.44     20:B3:99:55:9F:D9    ge.8.6            lldp



One can even see the mac addresses of devices via the uplink port from the problematic switch:

sw-ctdc-3rd-1(su)->show mac port ge.1.44


MAC Address       FID  Port          Type

----------------- ---- ------------- --------

00-00-5E-00-01-FA 1250 ge.1.44       Learned

00-10-F3-39-A3-40 1250 ge.1.44       Learned

00-10-F3-3F-0A-DE 1250 ge.1.44       Learned

00-11-88-1C-56-75 1250 ge.1.44       Learned

00-11-88-1C-56-ED 1250 ge.1.44       Learned

00-11-88-2C-32-B1 1250 ge.1.44       Learned

00-11-88-39-CB-6C 1250 ge.1.44       Learned

00-11-88-A9-F7-F0 1250 ge.1.44       Learned

00-11-88-ED-D4-AC 1250 ge.1.44       Learned

00-11-88-F6-7B-18 1250 ge.1.44       Learned

20-B3-99-55-49-AE 1250 ge.1.44       Learned

20-B3-99-55-9C-97 1250 ge.1.44       Learned

20-B3-99-55-9F-D9 1250 ge.1.44       Learned

20-B3-99-56-A8-E5 1250 ge.1.44       Learned

78-AC-C0-F1-4A-8F 1250 ge.1.44       Learned

B4-B5-2F-A5-2E-46 1250 ge.1.44       Learned

B4-B5-2F-A5-32-1A 1250 ge.1.44       Learned


And from the core it does learn the MAC of the problematic switch:

sw-ctdc-core1(su-router)->show mac port-string ge.8.6


MAC Address       FID  Port          Type    Status

----------------- ---- ------------- ------- -------

20-B3-99-55-49-AE 0    ge.8.6        self

00-1F-45-76-D5-68 1250 ge.8.6        learned



Even the Router portion on the core does see the swtich (but cannot ping it)  [Below is after I changed the local IP to

sw-ctdc-core1(su-router)->sh arp

LAGS:    U = Unresolved     S = Static

         L = Local          V = VRRP

          * = Stale          B = Best Guess Interface

          H = Host Interest  2 = Secondary VLAN Entry

          M = Main Router    A = Proxy-All Entry

          X = VxLan          R = VxLan Remote


IP Address      Hardware Address  Flg Age        Updated Interface      Port

--------------- ----------------- --- ---------- ------- -------------- -------------  00-1f-45-76-d5-68            20m     20m vlan.0.1250    ge.8.6

--------------- ----------------- --- ---------- ------- -------------- -------------

ARP Entries Found: 1




I tried the following:

  1. Deleted the vlan (thus setting host vlan to 1)
  2. Deleted the IP address and put another one on in the same range
  3. Set the port between this switch and the core to 100Mbps Full Duplex without any auto-negotiation.
  4. Set the ports on this switch and on the core to the management VLAN untagged.
  5. Disabled spanning tree on these ports.
  6. Clear arp all


The switches are on the latest firmware available.

The uptime is fairly recent as well: 66,8:18:55 

Any comments would be appreciated.
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Andre Brits Kannemeyer

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Posted 1 year ago

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