round robin dns, multihomed host, nfs mounting issues
Subsystems (2)
Client ip - 172.25.1.108
Server eth0 - 172.25.2.120 (default gateway 172.25.2.119) Server eth1 - 192.168.19.221
No firewall
OOT:beo408:/root# ps -ef | grep ipchain root 15474 13106 0 13:53 pts/0 00:00:00 grep ipchain ROOT:beo408:/root# ps -ef | grep iptable root 15476 13106 0 13:54 pts/0 00:00:00 grep iptable ROOT:beo408:/root# lsmod | grep ip ROOT:beo408:/root#
No /etc/hosts.allow or /etc/hosts.deny entries on server
rpcinfo -p localhost (on server)
program vers proto port
100000 2 tcp 111 portmapper
100000 2 udp 111 portmapper
100021 1 udp 32768 nlockmgr
100021 3 udp 32768 nlockmgr
100021 4 udp 32768 nlockmgr
100007 2 udp 630 ypbind
100007 1 udp 630 ypbind
100007 2 tcp 633 ypbind
100007 1 tcp 633 ypbind
100024 1 udp 836 status
100024 1 tcp 843 status
100001 3 udp 850 rstatd
100001 2 udp 850 rstatd
100001 1 udp 850 rstatd
100011 1 udp 748 rquotad
100011 2 udp 748 rquotad
100011 1 tcp 751 rquotad
100011 2 tcp 751 rquotad
100003 2 udp 2049 nfs
100003 3 udp 2049 nfs
100005 1 udp 833 mountd
100005 1 tcp 849 mountd
100005 2 udp 833 mountd
100005 2 tcp 849 mountd
100005 3 udp 833 mountd
100005 3 tcp 849 mountdROOT:beo408:/root# cat /etc/hosts.deny # # hosts.deny This file describes the names of the hosts which are # *not* allowed to use the local INET services, as decided # by the '/usr/sbin/tcpd' server. # # The portmap line is redundant, but it is left to remind you that # the new secure portmap uses hosts.deny and hosts.allow. In particular # you should know that NFS uses portmap!
ROOT:beo408:/root# cat /etc/hosts.allow # # hosts.allow This file describes the names of the hosts which are # allowed to use the local INET services, as decided # by the '/usr/sbin/tcpd' server. #
Non-local subnet client trying to talk to server eth1 interface
ROOT:beo408:/root# rpcinfo -u 192.168.19.221 mountd 3 rpcinfo: RPC: Port mapper failure - RPC: Timed out program 100005 version 3 is not available
ROOT:beo408:/root# rpcinfo -u 192.168.19.221 mountd 3 rpcinfo: RPC: Port mapper failure - RPC: Timed out program 100005 version 3 is not available
ROOT:beo408:/root# host beo408 beo408.ep.hess.com has address 172.25.1.108
ROOT:beo408:/root# rpcinfo -u 172.25.2.120 mountd 3 program 100005 version 3 ready and waiting
ROOT:beo408:/root# host 172.25.2.120 120.2.25.172.in-addr.arpa domain name pointer lfscluster01.ep.hess.com.
ROOT:beo408:/root# host 192.168.19.221 221.19.168.192.in-addr.arpa domain name pointer lfscluster01.ep.hess.com.
ROOT:beo408:/root# rpcinfo -u 192.168.19.221 mountd 3 rpcinfo: RPC: Port mapper failure - RPC: Timed out program 100005 version 3 is not available
Local subnet client trying to talk to server eth1 interface
Client ip - 192.168.19.1
Server eth0 - 172.25.2.120 (default gateway 172.25.2.119) Server eth1 - 192.168.19.221
eo001> host beo001
beo001.ep.hess.com has address 192.168.19.1
beo001> rpcinfo -u 192.168.19.221 mountd 3
program 100005 version 3 ready and waiting
beo001> rpcinfo -u 192.168.19.221 mountd 3
program 100005 version 3 ready and waiting
let's try 172.25.2.120 interface from 192.168.19 subnet
beo001> rpcinfo -u 172.25.2.120 mountd 3
program 100005 version 3 ready and waiting
this works, is it because this is the default gateway?
also, neil mentioned putting default route on each interface? is this ok?
thanks
previous messages follow
Quoted 2 lines · On Saturday July 19, [email protected] wrote:
Given Neil's comments about possible glibc bug and nfs 1.05, and my
sense that it is working, is it reasonable for me to think its working?
Quoted 2 lines
I.e should it work?
Maybe.
It is entirely possible that I mis-diagnosed your problem. If your NFS server is the only route between the two subnets, I probably did.
However I cannot think of any recent change in nfs-utils that would affect anything like your problem, but then my memory isn't perfect.
I suggest you test your configuration and if it works, be happy.
When I had the problem I mentioned, I used rpcinfo for testing:
rpcinfo -u $HOSTNAME mountd 3
If run this on a representative sample of clients, using a representative sample of server IP address, and it always works, then I guess your problem has gone away
NeilBrown
Quoted 5 lines · On July 18, [email protected] wrote:
I'm testing out a NFS server which has two interfaces on two different subnets. I'm using a single hostname and round robin dns. Clients are both RedHat Linux systems.
I can access the primary interface on server via NFS from any system
on
Quoted 3 lines
my network. I can only access the second interface from hosts on the same subnet. Unfortunately, round robin dns on systems that are not local to subnets on either of the server's nics will randomly get one
of
Quoted 11 lines
the two nics to access nfs fs through.
int 1 - 192.168.19.224
int 2 - 172.25.2.106# can mount through int 1 from any host\ # can mount thoughh int 2 from same ip subnet as int 2 # cannot mount throught int 2 from remote ip subnets # on local subnets, mounts work as desired through correct, optimal interface on nfs server
Quoted 4 lines
# on remote subnets, round robin directs ~50% of mount requests to server through int 2 which failwhy doesn't this work?
Looks like you've hit a glibc bug that was only fixed relatively recently (27th Feb 2003. glibc version 2.3.2 or 2.3.3 I think).
When mountd is sending it's reply, it uses sendmsg and insists that the reply goes out the same interface that the request came in on. If that interface doesn't have a route to the client, you lose.
I worked around it by putting a default route on all my interfaces.
Quoted 1 line
upgrading to nfs-utils 1.05 seems to have helped
I doubt that it really did, but if it works now, great.
NeilBrown
Signature · 17 lines
Jeff Davis Amerada Hess Corporation Global IT Technical Computing Infrastructure Houston, Texas [email protected] Office: 713-609-5436 Mobile: 281-467-9448 http://www.jrdavis.net/ ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ NFS maillist - [email protected] https://lists.sourceforge.net/lists/listinfo/nfs