No worries, thanks for quick response this time :) Unfortunately it seems that made no difference. I did: make clean git pull git apply patch_MTU.txt ./autogen.sh ./configure --with-vpnc-script=/usr/share/vpnc-scripts/vpnc-script make Just to make sure: $ ./openconnect -V OpenConnect version v7.08-3-ga01a167-dirty Using OpenSSL. Features present: TPM (OpenSSL ENGINE not present), HOTP software token, TOTP software token, DTLS $ grep buf_append_tlv_be32 oncp.c static void buf_append_tlv_be32(struct oc_text_buf *buf, uint16_t val, uint32_t data) buf_append_tlv_be32(reqbuf, 2, vpninfo->reqmtu); 1394 bytes Sent ESP packet of 116 bytes No work to do; sleeping for 10000 ms... Received ESP packet of 132 bytes No work to do; sleeping for 15000 ms... Sent ESP packet of 1444 bytes Sent ESP packet of 84 bytes No work to do; sleeping for 15000 ms... Received ESP packet of 1460 bytes No work to do; sleeping for 15000 ms... Sent ESP packet of 116 bytes No work to do; sleeping for 15000 ms... Received ESP packet of 164 bytes No work to do; sleeping for 15000 ms... 1395 bytes Sent ESP packet of 116 bytes No work to do; sleeping for 11000 ms... Received ESP packet of 132 bytes No work to do; sleeping for 15000 ms... Sent ESP packet of 1444 bytes Sent ESP packet of 100 bytes No work to do; sleeping for 15000 ms... Received ESP packet of 1460 bytes Received ESP packet with invalid HMAC No work to do; sleeping for 15000 ms... G. On 15. des. 2016 10:30, David Woodhouse wrote: > On Thu, 2016-12-15 at 10:00 +0100, Gaute Amundsen wrote: >> It seems 7.08 still has the same issue in my case. > Oops, apologies for missing that. > > This should probably fix the fact that --mtu doesn't work. Please > confirm, and I'll fix it. > > diff --git a/oncp.c b/oncp.c > index afcbe8b..249f8dc 100644 > --- a/oncp.c > +++ b/oncp.c > @@ -767,7 +767,7 @@ int oncp_connect(struct openconnect_info *vpninfo) > kmp = reqbuf->pos; > buf_append_tlv(reqbuf, 6, 0, NULL); /* TLV group 6 */ > group = reqbuf->pos; > - buf_append_tlv_be32(reqbuf, 2, vpninfo->ip_info.mtu); > + buf_append_tlv_be32(reqbuf, 2, vpninfo->reqmtu); > if (buf_error(reqbuf)) { > vpn_progress(vpninfo, PRG_ERR, > _("Error creating oNCP negotiation request\n")); > > >> With -vv >> >> ping -c1 -W 2 -s 1394 host.tld - succeeds >> >> Sent ESP packet of 116 bytes >> No work to do; sleeping for 10000 ms... >> Received ESP packet of 132 bytes >> No work to do; sleeping for 15000 ms... >> Sent ESP packet of 1444 bytes >> Sent ESP packet of 84 bytes >> No work to do; sleeping for 15000 ms... >> Received ESP packet of 1460 bytes >> No work to do; sleeping for 15000 ms... >> Sent ESP packet of 116 bytes >> No work to do; sleeping for 15000 ms... >> Received ESP packet of 164 bytes >> No work to do; sleeping for 15000 ms... >> >> >> ping -c1 -W 2 -s 1395 host.tld - fails >> >> Sent ESP packet of 116 bytes >> No work to do; sleeping for 4000 ms... >> Received ESP packet of 132 bytes >> No work to do; sleeping for 15000 ms... >> Sent ESP packet of 1444 bytes >> Sent ESP packet of 100 bytes >> No work to do; sleeping for 15000 ms... >> Received ESP packet of 1460 bytes >> Received ESP packet with invalid HMAC >> No work to do; sleeping for 15000 ms... > Hm, please could I have simultaneous captures of *both* the tun0 device > traffic, *and* the UDP Internet traffic between your public-facing > network adapter and the VPN server. Along with the verbose output of > openconnect where it gives the ESP keys I'll need to decrypt the > latter. > > Kill the session before you send the email (on general principles you > don't want to be giving out the keys to a live session), and try not to > have any other traffic on the VPN when you do it (partly for ease of > analysis, and partly because you don't want to show me anything else). > > You can send that in private mail if you prefer. Thanks. >