HP 1920 does not turn on ICMP redirect

[ewgenik]

HP 1920 does not turn on ICMP redirect

I enter in the CLI "ip redirects enable" - "Error: The operation is not supported."

I tried on 1920-24G and 1920-8G

Syntax okay -

[HP 1920G Switch]ip redirects ?
  enable  Enable the function

What's the trouble?

[16again]

Officially, CLI is not supported.  You're lucky when functions present in CLI but not in data sheet work....like RIP and OSPF

But do you really really need redirect?
-Sending a redirect packet costs switch CPU,  just routing to correct gateway is done in switch hardware at wire speed.
-Some hosts don't like redirect and keep sending traffic to wrong gateway. This might overwhelm HP1920 with huge amount of redirects to send.
-redirect is for /32 routes only.  For each new destination IP , a redirect needs to be sent, adding a /32 route to host route table
-What's the gain for redirected host directly connected to 1920?  With redirect, the switch will switch, without redirect, the switch will route at same speed. There's no shorter path.

[tech637]

Hi,

The icmp redirect is enabled in web.

Static route is defined with /32 mask.

However no icmp redirects seen, not by sniffer, nor in statistics.

Configured Route Summary Help
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rowsShowing 1 to 2 of 2 entriesFilter:

Network Address
Subnet Mask
Next Hop IP Address
Next Hop Interface
Preference
0.0.0.0 0.0.0.0 10.48.0.1 VLAN- 48 253
10.80.0.10 255.255.255.255 192.168.210.2 VLAN- 901 1

Sniffer shows that ping reply comes from 192.168.210.21 to 10.80.0.10, and not redirect as expected.