Loop in /24 Subnet, No ping beyond .1 and .2

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Special Forums IP Networking Loop in /24 Subnet, No ping beyond .1 and .2
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Old 04-13-2017
Loop in /24 Subnet, No ping beyond .1 and .2

Running 3650 switch. I have this odd issue where I cannot get 4 new Centos 7 boxes pinging out on public IPs (nor pinging in), only gateway .1 and first public IP .2

This is what I see, which doesn't look normal. How do I fix this?

The server itself is configured fine (Centos 7)

[root@localhost ~]# cat /etc/sysconfig/network-s*/ifcfg-em1

[root@localhost ~]# cat /etc/resolv.conf
# Generated by NetworkManager


Cisco3650#show ip route xxx.xxx.30.0
Routing entry for xxx.xxx.30.0/24, 2 known subnets
  Attached (2 connections)
  Variably subnetted with 2 masks
C        xxx.xxx.30.0/24 is directly connected, Vlan26
L        xxx.xxx.30.1/32 is directly connected, Vlan26

I don't know why that /32 is there. This is odd. I only assigned a /24, not that /32 and I cannot find the /32 anywhere.

Show run looks normal.

Cisco3650#show run int vlan 26
Building configuration...

Current configuration : 85 bytes
interface Vlan26
 description Server 26
 ip address xxx.xxx.30.1

This is happening to all four new VLANs I created last week, all 4 are running Centos 7 servers. That's odd. None of their assigned IPs ping past the first public IP. The rest show this same error.

[root@localhost ~]# ping xxx.xxx.107.59
PING xxx.xxx.107.59 (xxx.xxx.107.59) 56(84) bytes of data.
From xxx.xxx.107.58 icmp_seq=1 Destination Host Unreachable
From xxx.xxx.107.58 icmp_seq=2 Destination Host Unreachable
From xxx.xxx.107.58 icmp_seq=3 Destination Host Unreachable
From xxx.xxx.107.58 icmp_seq=4 Destination Host Unreachable

I tried another Centos 7 server on the same switch, same issue where I can only ping internally the gateway .1 and first public .2, or in this subnet (/29) case, I can ping gateway .129 and main IP .130 but not 132 - 134.

Cisco3650#show ip route xxx.xxx.107.130
Routing entry for xxx.xxx.107.128/29
  Known via "connected", distance 0, metric 0 (connected, via interface)
  Routing Descriptor Blocks:
  * directly connected, via Vlan24
      Route metric is 0, traffic share count is 1

Is this an issue with Centos 7? I tried Google DNS and also the data center's DNS. Same thing (I did 'service network restart' first before re-testing ping).
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