Bug 795653

Summary: Cannot delete ARP entries
Product: Red Hat Enterprise Linux 5 Reporter: Takasimadaira <littlebeastml>
Component: net-toolsAssignee: Jiri Popelka <jpopelka>
Status: CLOSED NOTABUG QA Contact: qe-baseos-daemons
Severity: high Docs Contact:
Priority: unspecified    
Version: 5.5   
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2012-03-20 15:26:20 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Takasimadaira 2012-02-21 07:39:50 UTC 
Description of problem:
I want to delete ARP entries manually. And I can not delete it successfully.
(1)Is my step of deletion correct?
(2)How long is ARP cache timeout and delete it automaticlly?

Version-Release number of selected component (if applicable):
#arp -V
net-tools 1.60
arp 1.88 (2001-04-04)
+I18N
AF: (inet) +UNIX +INET +INET6 +IPX +AX25 +NETROM +X25 +ATALK +ECONET +ROSE
HW: (ether) +ETHER +ARC +SLIP +PPP +TUNNEL +TR +AX25 +NETROM +X25 +FR +ROSE +ASH +SIT +FDDI +HIPPI +HDLC/LAPB

How reproducible:
Always

Steps to Reproduce:
1.From Server#1 ping Server#2
#ping <server_hostname>

2.check arp table at Server#2
#arp -v
Address                  HWtype  HWaddress           Flags Mask            Iface
aaa.aaa.aaa.a            ether   xx:xx:xx:xx:xx:xx   C                     bond2
bbb.bbb.b.b              ether   xx:xx:xx:xx:xx:xx   C                     bond2
Entries: 2      Skipped: 0      Found: 2

3.delete entry form Server#2
#arp -d aaa.aaa.aaa.a (it is Server#1's IP address)
  
Actual results:
SIOCDARP(priv): Network is unreachable 

Expected results:
Delete it successfully

Additional info:
Comment 1 Jiri Skala 2012-03-20 08:23:08 UTC 
The arp binary is a parto of net-tools.
Comment 2 Jiri Popelka 2012-03-20 15:24:39 UTC 
(In reply to comment #0)
> (1)Is my step of deletion correct?
Yes, I think so. It works for me without any problems.
You could also use 'ip neigh' instead of arp command.
example:
'ip neigh show' (instead of 'arp -v')
'ip neigh del aaa.aaa.aaa.a dev bond2' instead of 'arp -d aaa.aaa.aaa.a'

> (2)How long is ARP cache timeout and delete it automaticlly?
See [1] 

> Actual results:
> SIOCDARP(priv): Network is unreachable 
I tried to search web and found [1] which should answer this.

[1] http://geekstutorials.com/2008/12/how-to-delete-an-entry-from-arp-cache-manually-in-linux/
Comment 3 Jiri Popelka 2012-03-20 15:26:20 UTC 
Closing per previous comment.
Comment 4 Takasimadaira 2012-03-21 01:24:28 UTC 
Thank you for your help.I will try it in my server