- Community Home
- >
- Servers and Operating Systems
- >
- Operating System - HP-UX
- >
- Networking
- >
- Dead gateway detection messages in syslog
-
-
Forums
- Products
- Servers and Operating Systems
- Storage
- Software
- Services
- HPE GreenLake
- Company
- Events
- Webinars
- Partner Solutions and Certifications
- Local Language
- China - 简体中文
- Japan - 日本語
- Korea - 한국어
- Taiwan - 繁體中文
-
- Advancing Life & Work
- Advantage EX
- Alliances
- Around the Storage Block
- HPE Ezmeral: Uncut
- OEM Solutions
- Servers & Systems: The Right Compute
- Tech Insights
- The Cloud Experience Everywhere
- HPE Blog, Austria, Germany & Switzerland
- Blog HPE, France
- HPE Blog, Italy
- HPE Blog, Japan
- HPE Blog, Middle East
- HPE Blog, Latin America
- HPE Blog, Russia
- HPE Blog, Saudi Arabia
- HPE Blog, South Africa
- HPE Blog, UK & Ireland
- HPE Blog, Poland
-
Blogs
- Advancing Life & Work
- Advantage EX
- Alliances
- Around the Storage Block
- HPE Blog, Latin America
- HPE Blog, Middle East
- HPE Blog, Saudi Arabia
- HPE Blog, South Africa
- HPE Blog, UK & Ireland
- HPE Ezmeral: Uncut
- OEM Solutions
- Servers & Systems: The Right Compute
- Tech Insights
- The Cloud Experience Everywhere
-
Information
- Community
- Welcome
- Getting Started
- FAQ
- Ranking Overview
- Rules of Participation
- Tips and Tricks
- Resources
- Announcements
- Email us
- Feedback
- Information Libraries
- Integrated Systems
- Networking
- Servers
- Storage
- Other HPE Sites
- Support Center
- Aruba Airheads Community
- Enterprise.nxt
- HPE Dev Community
- Cloud28+ Community
- Marketplace
-
Forums
-
Forums
-
Blogs
-
Information
-
English
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
02-19-2014 03:09 AM
02-19-2014 03:09 AM
Hi
We lost nw connectivity to a vPAR yesterday afternoon, and at the same time these messages started to appear in the syslog.
Feb 19 04:34:15 MYHOST vmunix: Dead gateway detection can't ping the last remaining default gateway at 0xac1402c8 .See ndd -h ip_ire_gw_probe for more info
The hex address is the gateway configured.
The network team have checked everything they can, and find no faults. The lights are flashing on the NIC. The server is up as I can connect via the console.
Any ideas?
Do I need to set the ip_ire_gw_probe to '0', as I don't think this will make a difference, but I could be wrong.
Regards
Tariq
Solved! Go to Solution.
- Tags:
- gateway
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
02-19-2014 03:31 AM
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
02-19-2014 01:04 PM
02-19-2014 01:04 PM
Re: Dead gateway detection messages in syslog
I would turn off dead gateway detection on all servers. I find that it doesn't serve any useful purpose the majority of the time. If dead gateway detection determinues that the router is down (not pinging) then it will disable that route. If that is your only route to the outside world, you are hosed.
If your router really is down, then I suspect you will know about it pretty quick without the HP-UX server disabling your gateway.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
02-20-2014 03:20 AM
02-20-2014 03:20 AM
Re: Dead gateway detection messages in syslog
Thanks Patrick.
It was something on the Network end of things.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
02-20-2014 08:11 PM
02-20-2014 08:11 PM
Re: Dead gateway detection messages in syslog
This is an old default setting that should never have existed. The network code regularly pings routers to see if they are alive (even though ping is a primitive and useless test). When the router fails to respond, the network code assumes that the router is dead and stops using that route (an even more useless action). It is not unusual for network security to disable ICMP response (ie, ping) but with this setting in HP-UX, all routed traffic is halted because of a missed ping.
Yes, you need to set the dead gateway detect to off on *every* HP-UX server you have.
To make the change permanent, edit the nddconf file in /etc/rc.config.d and add this:
TRANSPORT_NAME[0]=ip
NDD_NAME[0]=ip_ire_gw_probe
NDD_VALUE[0]=0
The above assumes that there are no [0] entries already.
If there are, use the next available array reference such as [1] or [2].
Then run: ndd -c
which reads the file and performs the settings.
This sets the value to 0 and validates that the file is of the proper format.
(Did I mention that *every* HP-UX server needs this fix?)
Bill Hassell, sysadmin
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Email to a Friend
- Report Inappropriate Content
03-11-2014 02:47 AM
03-11-2014 02:47 AM
Re: Dead gateway detection messages in syslog
Hello,
Our colleague in the forum Bill Hassell is right. This can be a dangerous
problem if ignored.
As number of customers disable ICMP on internal networks (I worked with
many of those), it is becoming important to set it up properly when servers
are commissioned.
Because of that, I leared to test it when doing so-called Operations Acceptance Testing
for servers before they go into production:
http://www.circlingcycle.com.au/Unix-sources/HP-UX-check-OAT.pl.txt
Checking Deat Gateway Detect is a compulsory test for me.
Cheers,
VK2COT Dusan Baljevic
Hewlett Packard Enterprise International
- Communities
- HPE Blogs and Forum
© Copyright 2022 Hewlett Packard Enterprise Development LP