On Thu, May 21, 2026 at 10:24 PM Daniel Braniss <[email protected]> wrote:
On 21 May 2026, at 22:02, Bjoern A. Zeeb <[email protected]> wrote:
On Thu, 21 May 2026, Daniel Braniss wrote:
have several bhives and my workstation, running diskless, the server is also freebsd,
and very often, they hang on nfs, (I assume trying to access the root).
having them boot locally, and everything else, ie. /usr/local, home directory are nfs mounted without issues.
i’ll try and do a tcpdump but in the meantime any isights are welcome.
When do they hang? During boot? Or during operation?
during normal operation.
If they hang on an interactive command try ^T and see.
since root is nfs mounted, and it’s hung, nothing but power cycling works.
If tcpdump doesn't help much I'd start turning off checksum offloads and the like
along the path (unclear if your host is your nfs server or not) to see if that helps.
some more info:
the server is running 14.3 (i don’t think this is relevant)
the server us also providing /usr/local
if the host is running with a local root, all is fine.
virtual hosts, i.e bhive, also hang under similar configuration.
so now i'm running a tcpdump on the server, and will probably have more info.
That should give you more information. A few things to note:- 15.1 has the capability of using NFSv4 for root, but that requires some careful configuration.- Assuming your root is NFSv3 (you'll see that in the packet capture in wireshark), make sure you are not running nfsuserd(8) or gssd(8).
only NFS3 Both of these will try and look up user/group names in the passwd/group
file and this can hang the system when they do the upcall from within
the NFS client (which would have to access the files).
rick
so it hanged, im attaching the relevant tcpdump, what is weird, and I must have forgotten much, nrnd is the server, chamsa is the client. it seems nrnd is requesting arp too often … is the TTL on the arp reseted when a packet is received, or it just times out? here is the abridged version: |
hang