- Community Home
- >
- Servers and Operating Systems
- >
- Operating Systems
- >
- Operating System - Linux
- >
- Re: loopback IP entry in /ec/hosts
Categories
Company
Local Language
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Discussions
Discussions
Forums
Forums
Discussions
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Community
Resources
Forums
Blogs
- 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
- Report Inappropriate Content
тАО04-25-2011 10:37 AM
тАО04-25-2011 10:37 AM
loopback IP entry in /ec/hosts
For some reason or another, a client has the following entry in their Linux hosts. And it sems to be questioned by NetBackup support as the culprit in some backups failing.
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 sapsrv1.xyz.com sapsrv localhost.localdomain local
host
::1 localhost6.localdomain6 localhost6
10.201.100.100 sapsrv1.xyz.com sapsrv1
resolver for host is : files dns
TIA.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-25-2011 11:39 AM
тАО04-25-2011 11:39 AM
Re: loopback IP entry in /ec/hosts
Jeff Traigle
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-26-2011 03:01 AM
тАО04-26-2011 03:01 AM
Re: loopback IP entry in /ec/hosts
127.0.0.1 sapsrv1.xyz.com sapsrv localhost.localdomain local
host
BE
127.0.0.1 sapsrv1.xyz.com sapsrv1 localhost.localdomain local
host
Notice sapsrv1 not sapsrv
Enjoy life
Jean-Pierre Huc
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-26-2011 03:26 AM
тАО04-26-2011 03:26 AM
Re: loopback IP entry in /ec/hosts
If the hostname is not associated to an usable IP address when the system is starting up, some daemons and other applications may fail to start properly.
In a system that uses DHCP or is mobile (so it might not have no network connection at all sometimes!), the only guaranteed always-available IP addresses are the 127.*.*.* addresses.
Some Linux distributions (e.g. Debian 6.0) leave the 127.0.0.1 strictly for "localhost", and associate the hostname to 127.0.1.1: since all the 127.*.*.* addresses work as loopback addresses, this works.
If your system has statically configured IP addresses, you're free to remove the hostname from the 127.0.0.1 line and to associate it with the system's permanent IP address only.
But if your IP addresses are assigned with DHCP, you should at least test what happens if the system is booted when the DHCP server does not respond and the previous lease information (often stored persistently in e.g. /var/lib/dhcp) is expired or deleted.
MK
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-26-2011 05:53 AM
тАО04-26-2011 05:53 AM
Re: loopback IP entry in /ec/hosts
Doen't localhost.localdomain in the loopback IP "satisfy" most network services' need for a FQDN including sendmail if server is off network?
Symantec contends and I do agree (all our UNIX servers in my other clents do not have any other entry in the loopback address aside from localhost.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО04-26-2011 04:11 PM
тАО04-26-2011 04:11 PM
Re: loopback IP entry in /ec/hosts
For example inside
Note 1496410 - Red Hat Enterprise Linux 6: Installation and Upgrade
https://service.sap.com/sap/support/notes/1496410
see the section 'Hostname'...