Filed as 
misc/167947

On May 12, 2012, at 10:21 AM, Nikolay Denev wrote:

> On Jan 21, 2010, at 6:16 PM, Matt Burke wrote:
> 
>> Box is running 8.0-RELEASE-p2 cvsupped two days ago.
>> 
>> NICs are em bonded with lagg failover and running a few vlan interfaces.
>> 
>> net.my_fibnum: 0
>> net.add_addr_allfibs: 1
>> net.fibs: 4
>> 
>> This is reproducible, but with the lack of (accessible?) documentation on
>> multiple routing tables, I don't know if this is intended behaviour or a bug.
>> 
>> It seems processes using a non-default fib cannot perform arp lookups
>> unless the fib 0 has a routing table entry for the attached network:
>> 
>> [root@host ~]# ifconfig vlan11 a.a.a.92/27
>> [root@host ~]# route delete -net a.a.a.64/27
>> delete net a.a.a.64
>> [root@host ~]# setfib 1 ping a.a.a.65
>> PING a.a.a.65 (a.a.a.65): 56 data bytes
>> ping: sendto: Invalid argument
>> ^C
>> --- a.a.a.65 ping statistics ---
>> 1 packets transmitted, 0 packets received, 100.0% packet loss
>> [root@host ~]# dmesg |tail -1
>> arpresolve: can't allocate llinfo for a.a.a.65
>> 
>> 
>> Putting the entry into the arp cache before removing the route results in
>> success:
>> 
>> [root@host ~]# ifconfig vlan11 a.a.a.92/27
>> [root@host ~]# setfib 1 ping a.a.a.65
>> PING a.a.a.65 (a.a.a.65): 56 data bytes
>> 64 bytes from a.a.a.65: icmp_seq=0 ttl=255 time=1.437 ms
>> ^C
>> --- a.a.a.65 ping statistics ---
>> 1 packets transmitted, 1 packets received, 0.0% packet loss
>> round-trip min/avg/max/stddev = 1.437/1.437/1.437/0.000 ms
>> [root@host ~]# route delete -net a.a.a.64/27
>> delete net a.a.a.64
>> [root@host ~]# setfib 1 ping a.a.a.65
>> PING a.a.a.65 (a.a.a.65): 56 data bytes
>> 64 bytes from a.a.a.65: icmp_seq=0 ttl=255 time=0.762 ms
>> ^C
>> --- a.a.a.65 ping statistics ---
>> 1 packets transmitted, 1 packets received, 0.0% packet loss
>> round-trip min/avg/max/stddev = 0.762/0.762/0.762/0.000 ms
>> 
>> 
>> and deleting it again results in failure:
>> 
>> [root@host ~]# arp -an
>> ? (a.a.a.92) at 00:11:27:00:d7:c4 on vlan11 permanent [vlan]
>> ? (a.a.a.65) at 00:1a:e4:00:60:bf on vlan11 [vlan]
>> ...
>> [root@host ~]# arp -d a.a.a.65
>> delete: cannot locate a.a.a.65
>> [root@host ~]# setfib 1 arp -d a.a.a.65
>> a.a.a.65 (a.a.a.65) deleted
>> [root@host ~]# setfib 1 ping -c1 a.a.a.65
>> PING a.a.a.65 (a.a.a.65): 56 data bytes
>> ping: sendto: Invalid argument
>> ^C
>> --- a.a.a.65 ping statistics ---
>> 1 packets transmitted, 0 packets received, 100.0% packet loss
>> 
>> 
>> This behaviour seems a little inconsistent, with fib 1 requesting arp
>> lookups, fib 0 performing and displaying them, but fib 1 needing to delete
>> them...
>> 
>> 
>> 
>> -- 
>> 
>> The information contained in this message is confidential and is intended 
>> for the addressee only. If you have received this message in error or there 
>> are any problems please notify the originator immediately. The unauthorised 
>> use, disclosure, copying or alteration of this message is strictly 
>> forbidden. 
>> 
>> Critical Software Ltd. reserves the right to monitor and record e-mail 
>> messages sent to and from this address for the purposes of investigating or 
>> detecting any unauthorised use of its system and ensuring its effective 
>> operation.
>> 
>> Critical Software Ltd. registered in England, 04909220. Registered Office: 
>> IC2, Keele Science Park, Keele, Staffordshire, ST5 5NH.
>> 
>> ------------------------------------------------------------
>> This message has been scanned for security threats by iCritical.
>>   For further information, please visit www.icritical.com
>> ------------------------------------------------------------
> 
> I've encountered exactly the same problem today.
> 
> I have a machine with public addresses, and also a interface for out of band 
> management with private address, and I wanted to use
> a separate FIB for the private interface and it's routes.
> 
> When I've deleted the routes for the private interface form the main FIB, 
> arpresolve stopped working.
> 
> The I've patched sys/netinet/in.c with the following patch :
> 
> --- sys/netinet/in.c.orig     2012-05-12 08:57:17.000000000 +0200
> +++ sys/netinet/in.c  2012-05-12 08:56:43.000000000 +0200
> @@ -1418,21 +1418,21 @@
> 
> static int
> in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr 
> *l3addr)
> {
>       struct rtentry *rt;
> 
>       KASSERT(l3addr->sa_family == AF_INET,
>           ("sin_family %d", l3addr->sa_family));
> 
>       /* XXX rtalloc1 should take a const param */
> -     rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
> +     rt = rtalloc1_fib(__DECONST(struct sockaddr *, l3addr), 0, 0, 
> ifp->if_fib);
> 
>       if (rt == NULL)
>               return (EINVAL);
> 
>       /*
>        * If the gateway for an existing host route matches the target L3
>        * address, which is a special route inserted by some implementation
>        * such as MANET, and the interface is of the correct type, then
>        * allow for ARP to proceed.
>        */
> 
> 
> And this seems to fix the issue.
> 
> Now that the multi FIB code is in GENERIC probably this (or similar fix) 
> should be comitted.
> 
> P.S.: I also wonder why the loopback route for an interface address is also 
> installed explicitly in the default FIB?
> 
> 
> 

_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"

Reply via email to