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source ip in arp who-has request not valid

 
psa14
New Member

source ip in arp who-has request not valid

Hi,

my switch is a procurve 2626.
When i want to ping a PC from lan 192.168.10.x to lan 192.168.22.x it works.
But when i want to ping a network equipement
from lan 192.168.10.x to lan 192.168.22.x it doesn't work (Such as switchs, wifi equipement ...).

I have 2 VLANs (vlan 1 and vlan 2)
On the vlan 1, i have 4 subnets :
192.168.1.x, gw 192.168.1.33
192.168.10.x, gw 192.168.10.253
192.168.22.x, gw 192.168.22.254
192.168.21.x, gw 192.168.21.254

Routing is enable

The procurve switch has 4 IPs addresses :
192.168.1.33, 192.168.10.253, 192.168.22.254,
192.168.21.254

I sniff the subnet 192.168.22.x and see that
the arp request looks like :
procurve-mac-> broadcast who-has 192.168.22.33 ? tell 192.168.1.33

I think the problem is from the source in the request. Why the procurve uses 192.168.1.33 as source and not 192.168.22.254 ? Is there a parameter on the switch to modify ?


Thanks

Pascal
4 REPLIES 4
Pieter 't Hart
Honored Contributor

Re: source ip in arp who-has request not valid

this is because the order that adresses are assigned
it will use the primary adress for arp requests, not separate secondary adresses for each matching subnet.

from 2600-2800-4100-6108-MgmtConfigGde:
The switch assigns the first IP address manually configured on a VLAN as the primary IP address. The switch then assigns any subsequent IP addresses (for other subnets) manually configured on the VLAN as secondary
addresses.

psa14
New Member

Re: source ip in arp who-has request not valid

Hi Peter,
thanks for you response,

i fact, i want this switch acts as rounting between 4 physical networks.
I want to route packets from and to the 4 networks in the vlan 1.
1.x<->10.x
1.x<->22.x
1.x<->21.x
10.x<->22.x
21.x<->22.x
10.x<->21.x

The vlan2 exists on the 4 networks, but there are one subnet.

I have made a test ping between subnet 10.x
and subnet 22.x. It works only for pc
equipement and not for other network equipement.

Is it possible with the procurve ?

Thanks
Pieter 't Hart
Honored Contributor

Re: source ip in arp who-has request not valid

Just beacause it's not separate (sub)interfaces, but secondary adresses on a single interface , I think the 2626 may not route between primary/secondary and between secondary/secondary adresses.

what output does "show ip route" produce?.
Eric Plikuhn
New Member

Re: source ip in arp who-has request not valid

I see the same on a number of my Procurve switches:

Switch configuration:
vlan 1
name "Local"
untagged 1-18
ip address 1.2.3.4 255.255.255.0
ip address 10.118.254.254 255.255.0.0

Packet dump:
Who has 10.118.0.47? Tell 1.2.3.4

Unfortunately some equipment will not respond to the ARP request since the address is out of the subnet.

Have you found a solution for this?