Description of problem:

/sbin/ip shows 32-bit statistics, even on 64-bit kernel.


Version-Release number of selected component (if applicable):

For this kernel/iproute/net-tools combination on my test rig:

[root@trafalgar-centos65-x86-64 ~]# uname -a 
Linux trafalgar-centos65-x86-64.bugfinder.co.uk 2.6.32-431.el6.x86_64 #1 SMP Fri Nov 22 03:15:09 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
[root@trafalgar-centos65-x86-64 ~]# 

iproute-2.6.32-31.el6.x86_64

net-tools-1.60-110.el6_2.x86_64


How reproducible:

Having pumped about 5GB of data in to a test CentOS6.5 x86_64 instance, I could see that /sbin/ifconfig reported >4GB of Rx Bytes, whilst "/sbin/ip -s link show" reported 600MB, indicating that ifconfig is using a 64-bit counter whilst /sbin/ip is using a 32-bit counter.

FWIW, SNMP interfaces MIB still reports a 32-bit Counter, but that's to be expected as it's defined as 32-bit in the MIB, but the HC-MIB does report 64-bit Counters on x86_64 as shown by the tests below.


[root@trafalgar-centos65-x86-64 ~]# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:1C:42:91:BE:74 
          inet addr:10.211.55.8  Bcast:10.211.55.255  Mask:255.255.255.0
          inet6 addr: fe80::21c:42ff:fe91:be74/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3455650 errors:0 dropped:0 overruns:0 frame:0
          TX packets:463111 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4931589231 (4.5 GiB)  TX bytes:33046767 (31.5 MiB)

[root@trafalgar-centos65-x86-64 ~]#


[root@trafalgar-centos65-x86-64 ~]# ip -s link show eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:1c:42:91:be:74 brd ff:ff:ff:ff:ff:ff
    RX: bytes  packets  errors  dropped overrun mcast  
    636623473  3455667  0       0       0       1     
    TX: bytes  packets  errors  dropped carrier collsns
    33048677   463120   0       0       0       0     
[root@trafalgar-centos65-x86-64 ~]#


FWIW, neither ifconfig nor /sbin/ip nor SNMP HC-MIB report 64-bit Counters on 32-bit Kernels, but I understand that part of the reason for that may be difficulties in updating a 64-bit kernel variable atomically on a 32-bit ARCH.

It would be good, in my view, to not support HC-MIB on 32-bit ARCH unless it can report a true 64-bit Counter, but that may be something of a religious argument :)




[root@trafalgar-centos65-x86-64 ~]# snmpwalk -c public -v 2c localhost interfaces | grep Octets
IF-MIB::ifInOctets.1 = Counter32: 0
IF-MIB::ifInOctets.2 = Counter32: 636619429
IF-MIB::ifOutOctets.1 = Counter32: 0
IF-MIB::ifOutOctets.2 = Counter32: 33042059
[root@trafalgar-centos65-x86-64 ~]#

[root@trafalgar-centos65-x86-64 ~]# snmpwalk -c public -v 2c localhost .1.3.6.1.2.1.31  | grep Octets
IF-MIB::ifHCInOctets.1 = Counter64: 13572
IF-MIB::ifHCInOctets.2 = Counter64: 4931600285
IF-MIB::ifHCOutOctets.1 = Counter64: 13572
IF-MIB::ifHCOutOctets.2 = Counter64: 33058003
[root@trafalgar-centos65-x86-64 ~]#