Date: Fri, 12 Nov 2021 17:31:00 UTC
Hi! > >> OK. Can you provide the output of > >> netstat -sptcp > >> after some packets were dropped. > Not sure why you provide two outputs. I did on the dest host: netstat -sptcp then a few telnet <dest-ip> 179 then a second netstat -sptcp That's why I provided two outputs. There's one small diff between the two that I do not understand: - 18040 times no signature provided by segment + 18045 times no signature provided by segment > Does 'the discarded for bad checksums' counter increase No 8-( > If you capture the incoming traffic with Wireshark, does it report that > the checksum is wrong? No, it says: # tcpdump -i vlan500 -n -s 1500 -vvX port 179 and host <source-ip> tcpdump: listening on vlan500, link-type EN10MB (Ethernet), capture size 1500 bytes 18:24:37.947459 IP (tos 0x10, ttl 64, id 0, offset 0, flags [DF], proto TCP (6), length 60) <source-ip>.21692 > <dest-ip>.179: Flags [S], cksum 0x33b8 (correct), seq 2286661000, win 65535, options [mss 1460,nop,wscale 9,sackOK,TS val 286146398 ecr 0], length 0 0x0000: 4510 003c 0000 4000 4006 0216 d447 c801 E..<..@.@....G.. 0x0010: d447 c805 54bc 00b3 884b ad88 0000 0000 .G..T....K...... 0x0020: a002 ffff 33b8 0000 0204 05b4 0103 0309 ....3........... 0x0030: 0402 080a 110e 3f5e 0000 0000 ......?^.... > > On the same 10g ix0 interface we have three VLANs: > > - one (vlan551) of them uses tcp-md5 for another bgp session > > - one (vlan500) does not use tcp-md5, and has the problem > > - one (vlan724) does not use tcp-md5 for bgp, and works fine > Possibly the usage of vlans is relevant for this issue. Not sure. This is the driver we're using: dev.ix.0.%desc: Intel(R) PRO/10GbE PCI-Express Network Driver, Version - 3.3.24 -- pi@FreeBSD.org +49 171 3101372 Now what ?