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authorMatthieu Baerts <matthieu.baerts@tessares.net>2023-06-10 18:11:39 +0200
committerJakub Kicinski <kuba@kernel.org>2023-06-12 16:55:42 -0700
commit47867f0a7e831e24e5eab3330667ce9682d50fb1 (patch)
tree6424efcfd78011ada13d35ecc19f755253043f4e /tools
parentcdb50525345cf5a8359ee391032ef606a7826f08 (diff)
selftests: mptcp: join: skip check if MIB counter not supported
Selftests are supposed to run on any kernels, including the old ones not supporting all MPTCP features. One of them is the MPTCP MIB counters introduced in commit fc518953bc9c ("mptcp: add and use MIB counter infrastructure") and more later. The MPTCP Join selftest heavily relies on these counters. If a counter is not supported by the kernel, it is not displayed when using 'nstat -z'. We can then detect that and skip the verification. A new helper (get_counter()) has been added to do the required checks and return an error if the counter is not available. Note that if we expect to have these features available and if SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var is set to 1, the tests will be marked as failed instead of skipped. This new helper also makes sure we get the exact counter we want to avoid issues we had in the past, e.g. with MPTcpExtRmAddr and MPTcpExtRmAddrDrop sharing the same prefix. While at it, we uniform the way we fetch a MIB counter. Note for the backports: we rarely change these modified blocks so if there is are conflicts, it is very likely because a counter is not used in the older kernels and we don't need that chunk. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368 Fixes: b08fbf241064 ("selftests: add test-cases for MPTCP MP_JOIN") Cc: stable@vger.kernel.org Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'tools')
-rwxr-xr-xtools/testing/selftests/net/mptcp/mptcp_join.sh230
1 files changed, 130 insertions, 100 deletions
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index a63aed145393..276396cbe60c 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -500,11 +500,25 @@ wait_local_port_listen()
done
}
-rm_addr_count()
+# $1: ns ; $2: counter
+get_counter()
{
- local ns=${1}
+ local ns="${1}"
+ local counter="${2}"
+ local count
+
+ count=$(ip netns exec ${ns} nstat -asz "${counter}" | awk 'NR==1 {next} {print $2}')
+ if [ -z "${count}" ]; then
+ mptcp_lib_fail_if_expected_feature "${counter} counter"
+ return 1
+ fi
- ip netns exec ${ns} nstat -as | grep MPTcpExtRmAddr | awk '{print $2}'
+ echo "${count}"
+}
+
+rm_addr_count()
+{
+ get_counter "${1}" "MPTcpExtRmAddr"
}
# $1: ns, $2: old rm_addr counter in $ns
@@ -527,11 +541,11 @@ wait_mpj()
local ns="${1}"
local cnt old_cnt
- old_cnt=$(ip netns exec ${ns} nstat -as | grep MPJoinAckRx | awk '{print $2}')
+ old_cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
local i
for i in $(seq 10); do
- cnt=$(ip netns exec ${ns} nstat -as | grep MPJoinAckRx | awk '{print $2}')
+ cnt=$(get_counter ${ns} "MPTcpExtMPJoinAckRx")
[ "$cnt" = "${old_cnt}" ] || break
sleep 0.1
done
@@ -1190,12 +1204,13 @@ chk_csum_nr()
fi
printf "%-${nr_blank}s %s" " " "sum"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtDataCsumErr | awk '{print $2}')
- [ -z "$count" ] && count=0
+ count=$(get_counter ${ns1} "MPTcpExtDataCsumErr")
if [ "$count" != "$csum_ns1" ]; then
extra_msg="$extra_msg ns1=$count"
fi
- if { [ "$count" != $csum_ns1 ] && [ $allow_multi_errors_ns1 -eq 0 ]; } ||
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif { [ "$count" != $csum_ns1 ] && [ $allow_multi_errors_ns1 -eq 0 ]; } ||
{ [ "$count" -lt $csum_ns1 ] && [ $allow_multi_errors_ns1 -eq 1 ]; }; then
echo "[fail] got $count data checksum error[s] expected $csum_ns1"
fail_test
@@ -1204,12 +1219,13 @@ chk_csum_nr()
echo -n "[ ok ]"
fi
echo -n " - csum "
- count=$(ip netns exec $ns2 nstat -as | grep MPTcpExtDataCsumErr | awk '{print $2}')
- [ -z "$count" ] && count=0
+ count=$(get_counter ${ns2} "MPTcpExtDataCsumErr")
if [ "$count" != "$csum_ns2" ]; then
extra_msg="$extra_msg ns2=$count"
fi
- if { [ "$count" != $csum_ns2 ] && [ $allow_multi_errors_ns2 -eq 0 ]; } ||
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif { [ "$count" != $csum_ns2 ] && [ $allow_multi_errors_ns2 -eq 0 ]; } ||
{ [ "$count" -lt $csum_ns2 ] && [ $allow_multi_errors_ns2 -eq 1 ]; }; then
echo "[fail] got $count data checksum error[s] expected $csum_ns2"
fail_test
@@ -1251,12 +1267,13 @@ chk_fail_nr()
fi
printf "%-${nr_blank}s %s" " " "ftx"
- count=$(ip netns exec $ns_tx nstat -as | grep MPTcpExtMPFailTx | awk '{print $2}')
- [ -z "$count" ] && count=0
+ count=$(get_counter ${ns_tx} "MPTcpExtMPFailTx")
if [ "$count" != "$fail_tx" ]; then
extra_msg="$extra_msg,tx=$count"
fi
- if { [ "$count" != "$fail_tx" ] && [ $allow_tx_lost -eq 0 ]; } ||
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif { [ "$count" != "$fail_tx" ] && [ $allow_tx_lost -eq 0 ]; } ||
{ [ "$count" -gt "$fail_tx" ] && [ $allow_tx_lost -eq 1 ]; }; then
echo "[fail] got $count MP_FAIL[s] TX expected $fail_tx"
fail_test
@@ -1266,12 +1283,13 @@ chk_fail_nr()
fi
echo -n " - failrx"
- count=$(ip netns exec $ns_rx nstat -as | grep MPTcpExtMPFailRx | awk '{print $2}')
- [ -z "$count" ] && count=0
+ count=$(get_counter ${ns_rx} "MPTcpExtMPFailRx")
if [ "$count" != "$fail_rx" ]; then
extra_msg="$extra_msg,rx=$count"
fi
- if { [ "$count" != "$fail_rx" ] && [ $allow_rx_lost -eq 0 ]; } ||
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif { [ "$count" != "$fail_rx" ] && [ $allow_rx_lost -eq 0 ]; } ||
{ [ "$count" -gt "$fail_rx" ] && [ $allow_rx_lost -eq 1 ]; }; then
echo "[fail] got $count MP_FAIL[s] RX expected $fail_rx"
fail_test
@@ -1303,10 +1321,11 @@ chk_fclose_nr()
fi
printf "%-${nr_blank}s %s" " " "ctx"
- count=$(ip netns exec $ns_tx nstat -as | grep MPTcpExtMPFastcloseTx | awk '{print $2}')
- [ -z "$count" ] && count=0
- [ "$count" != "$fclose_tx" ] && extra_msg="$extra_msg,tx=$count"
- if [ "$count" != "$fclose_tx" ]; then
+ count=$(get_counter ${ns_tx} "MPTcpExtMPFastcloseTx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$fclose_tx" ]; then
+ extra_msg="$extra_msg,tx=$count"
echo "[fail] got $count MP_FASTCLOSE[s] TX expected $fclose_tx"
fail_test
dump_stats=1
@@ -1315,10 +1334,11 @@ chk_fclose_nr()
fi
echo -n " - fclzrx"
- count=$(ip netns exec $ns_rx nstat -as | grep MPTcpExtMPFastcloseRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- [ "$count" != "$fclose_rx" ] && extra_msg="$extra_msg,rx=$count"
- if [ "$count" != "$fclose_rx" ]; then
+ count=$(get_counter ${ns_rx} "MPTcpExtMPFastcloseRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$fclose_rx" ]; then
+ extra_msg="$extra_msg,rx=$count"
echo "[fail] got $count MP_FASTCLOSE[s] RX expected $fclose_rx"
fail_test
dump_stats=1
@@ -1349,9 +1369,10 @@ chk_rst_nr()
fi
printf "%-${nr_blank}s %s" " " "rtx"
- count=$(ip netns exec $ns_tx nstat -as | grep MPTcpExtMPRstTx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ $count -lt $rst_tx ]; then
+ count=$(get_counter ${ns_tx} "MPTcpExtMPRstTx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ $count -lt $rst_tx ]; then
echo "[fail] got $count MP_RST[s] TX expected $rst_tx"
fail_test
dump_stats=1
@@ -1360,9 +1381,10 @@ chk_rst_nr()
fi
echo -n " - rstrx "
- count=$(ip netns exec $ns_rx nstat -as | grep MPTcpExtMPRstRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" -lt "$rst_rx" ]; then
+ count=$(get_counter ${ns_rx} "MPTcpExtMPRstRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" -lt "$rst_rx" ]; then
echo "[fail] got $count MP_RST[s] RX expected $rst_rx"
fail_test
dump_stats=1
@@ -1383,9 +1405,10 @@ chk_infi_nr()
local dump_stats
printf "%-${nr_blank}s %s" " " "itx"
- count=$(ip netns exec $ns2 nstat -as | grep InfiniteMapTx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$infi_tx" ]; then
+ count=$(get_counter ${ns2} "MPTcpExtInfiniteMapTx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$infi_tx" ]; then
echo "[fail] got $count infinite map[s] TX expected $infi_tx"
fail_test
dump_stats=1
@@ -1394,9 +1417,10 @@ chk_infi_nr()
fi
echo -n " - infirx"
- count=$(ip netns exec $ns1 nstat -as | grep InfiniteMapRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$infi_rx" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtInfiniteMapRx")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$infi_rx" ]; then
echo "[fail] got $count infinite map[s] RX expected $infi_rx"
fail_test
dump_stats=1
@@ -1428,9 +1452,10 @@ chk_join_nr()
fi
printf "%03u %-36s %s" "${TEST_COUNT}" "${title}" "syn"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPJoinSynRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$syn_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPJoinSynRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$syn_nr" ]; then
echo "[fail] got $count JOIN[s] syn expected $syn_nr"
fail_test
dump_stats=1
@@ -1440,9 +1465,10 @@ chk_join_nr()
echo -n " - synack"
with_cookie=$(ip netns exec $ns2 sysctl -n net.ipv4.tcp_syncookies)
- count=$(ip netns exec $ns2 nstat -as | grep MPTcpExtMPJoinSynAckRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$syn_ack_nr" ]; then
+ count=$(get_counter ${ns2} "MPTcpExtMPJoinSynAckRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$syn_ack_nr" ]; then
# simult connections exceeding the limit with cookie enabled could go up to
# synack validation as the conn limit can be enforced reliably only after
# the subflow creation
@@ -1458,9 +1484,10 @@ chk_join_nr()
fi
echo -n " - ack"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPJoinAckRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$ack_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPJoinAckRx")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$ack_nr" ]; then
echo "[fail] got $count JOIN[s] ack expected $ack_nr"
fail_test
dump_stats=1
@@ -1492,12 +1519,12 @@ chk_stale_nr()
local recover_nr
printf "%-${nr_blank}s %-18s" " " "stale"
- stale_nr=$(ip netns exec $ns nstat -as | grep MPTcpExtSubflowStale | awk '{print $2}')
- [ -z "$stale_nr" ] && stale_nr=0
- recover_nr=$(ip netns exec $ns nstat -as | grep MPTcpExtSubflowRecover | awk '{print $2}')
- [ -z "$recover_nr" ] && recover_nr=0
- if [ $stale_nr -lt $stale_min ] ||
+ stale_nr=$(get_counter ${ns} "MPTcpExtSubflowStale")
+ recover_nr=$(get_counter ${ns} "MPTcpExtSubflowRecover")
+ if [ -z "$stale_nr" ] || [ -z "$recover_nr" ]; then
+ echo "[skip]"
+ elif [ $stale_nr -lt $stale_min ] ||
{ [ $stale_max -gt 0 ] && [ $stale_nr -gt $stale_max ]; } ||
[ $((stale_nr - recover_nr)) -ne $stale_delta ]; then
echo "[fail] got $stale_nr stale[s] $recover_nr recover[s], " \
@@ -1533,12 +1560,12 @@ chk_add_nr()
timeout=$(ip netns exec $ns1 sysctl -n net.mptcp.add_addr_timeout)
printf "%-${nr_blank}s %s" " " "add"
- count=$(ip netns exec $ns2 nstat -as MPTcpExtAddAddr | grep MPTcpExtAddAddr | awk '{print $2}')
- [ -z "$count" ] && count=0
-
+ count=$(get_counter ${ns2} "MPTcpExtAddAddr")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
# if the test configured a short timeout tolerate greater then expected
# add addrs options, due to retransmissions
- if [ "$count" != "$add_nr" ] && { [ "$timeout" -gt 1 ] || [ "$count" -lt "$add_nr" ]; }; then
+ elif [ "$count" != "$add_nr" ] && { [ "$timeout" -gt 1 ] || [ "$count" -lt "$add_nr" ]; }; then
echo "[fail] got $count ADD_ADDR[s] expected $add_nr"
fail_test
dump_stats=1
@@ -1547,9 +1574,10 @@ chk_add_nr()
fi
echo -n " - echo "
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtEchoAdd | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$echo_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtEchoAdd")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$echo_nr" ]; then
echo "[fail] got $count ADD_ADDR echo[s] expected $echo_nr"
fail_test
dump_stats=1
@@ -1559,9 +1587,10 @@ chk_add_nr()
if [ $port_nr -gt 0 ]; then
echo -n " - pt "
- count=$(ip netns exec $ns2 nstat -as | grep MPTcpExtPortAdd | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$port_nr" ]; then
+ count=$(get_counter ${ns2} "MPTcpExtPortAdd")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$port_nr" ]; then
echo "[fail] got $count ADD_ADDR[s] with a port-number expected $port_nr"
fail_test
dump_stats=1
@@ -1570,10 +1599,10 @@ chk_add_nr()
fi
printf "%-${nr_blank}s %s" " " "syn"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPJoinPortSynRx |
- awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$syn_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPJoinPortSynRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$syn_nr" ]; then
echo "[fail] got $count JOIN[s] syn with a different \
port-number expected $syn_nr"
fail_test
@@ -1583,10 +1612,10 @@ chk_add_nr()
fi
echo -n " - synack"
- count=$(ip netns exec $ns2 nstat -as | grep MPTcpExtMPJoinPortSynAckRx |
- awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$syn_ack_nr" ]; then
+ count=$(get_counter ${ns2} "MPTcpExtMPJoinPortSynAckRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$syn_ack_nr" ]; then
echo "[fail] got $count JOIN[s] synack with a different \
port-number expected $syn_ack_nr"
fail_test
@@ -1596,10 +1625,10 @@ chk_add_nr()
fi
echo -n " - ack"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPJoinPortAckRx |
- awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$ack_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPJoinPortAckRx")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$ack_nr" ]; then
echo "[fail] got $count JOIN[s] ack with a different \
port-number expected $ack_nr"
fail_test
@@ -1609,10 +1638,10 @@ chk_add_nr()
fi
printf "%-${nr_blank}s %s" " " "syn"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMismatchPortSynRx |
- awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$mis_syn_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMismatchPortSynRx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$mis_syn_nr" ]; then
echo "[fail] got $count JOIN[s] syn with a mismatched \
port-number expected $mis_syn_nr"
fail_test
@@ -1622,10 +1651,10 @@ chk_add_nr()
fi
echo -n " - ack "
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMismatchPortAckRx |
- awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$mis_ack_nr" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMismatchPortAckRx")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$mis_ack_nr" ]; then
echo "[fail] got $count JOIN[s] ack with a mismatched \
port-number expected $mis_ack_nr"
fail_test
@@ -1669,9 +1698,10 @@ chk_rm_nr()
fi
printf "%-${nr_blank}s %s" " " "rm "
- count=$(ip netns exec $addr_ns nstat -as | grep MPTcpExtRmAddr | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$rm_addr_nr" ]; then
+ count=$(get_counter ${addr_ns} "MPTcpExtRmAddr")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$rm_addr_nr" ]; then
echo "[fail] got $count RM_ADDR[s] expected $rm_addr_nr"
fail_test
dump_stats=1
@@ -1680,29 +1710,27 @@ chk_rm_nr()
fi
echo -n " - rmsf "
- count=$(ip netns exec $subflow_ns nstat -as | grep MPTcpExtRmSubflow | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ -n "$simult" ]; then
+ count=$(get_counter ${subflow_ns} "MPTcpExtRmSubflow")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ -n "$simult" ]; then
local cnt suffix
- cnt=$(ip netns exec $addr_ns nstat -as | grep MPTcpExtRmSubflow | awk '{print $2}')
+ cnt=$(get_counter ${addr_ns} "MPTcpExtRmSubflow")
# in case of simult flush, the subflow removal count on each side is
# unreliable
- [ -z "$cnt" ] && cnt=0
count=$((count + cnt))
[ "$count" != "$rm_subflow_nr" ] && suffix="$count in [$rm_subflow_nr:$((rm_subflow_nr*2))]"
if [ $count -ge "$rm_subflow_nr" ] && \
[ "$count" -le "$((rm_subflow_nr *2 ))" ]; then
- echo "[ ok ] $suffix"
+ echo -n "[ ok ] $suffix"
else
echo "[fail] got $count RM_SUBFLOW[s] expected in range [$rm_subflow_nr:$((rm_subflow_nr*2))]"
fail_test
dump_stats=1
fi
- return
- fi
- if [ "$count" != "$rm_subflow_nr" ]; then
+ elif [ "$count" != "$rm_subflow_nr" ]; then
echo "[fail] got $count RM_SUBFLOW[s] expected $rm_subflow_nr"
fail_test
dump_stats=1
@@ -1723,9 +1751,10 @@ chk_prio_nr()
local dump_stats
printf "%-${nr_blank}s %s" " " "ptx"
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPPrioTx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$mp_prio_nr_tx" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPPrioTx")
+ if [ -z "$count" ]; then
+ echo -n "[skip]"
+ elif [ "$count" != "$mp_prio_nr_tx" ]; then
echo "[fail] got $count MP_PRIO[s] TX expected $mp_prio_nr_tx"
fail_test
dump_stats=1
@@ -1734,9 +1763,10 @@ chk_prio_nr()
fi
echo -n " - prx "
- count=$(ip netns exec $ns1 nstat -as | grep MPTcpExtMPPrioRx | awk '{print $2}')
- [ -z "$count" ] && count=0
- if [ "$count" != "$mp_prio_nr_rx" ]; then
+ count=$(get_counter ${ns1} "MPTcpExtMPPrioRx")
+ if [ -z "$count" ]; then
+ echo "[skip]"
+ elif [ "$count" != "$mp_prio_nr_rx" ]; then
echo "[fail] got $count MP_PRIO[s] RX expected $mp_prio_nr_rx"
fail_test
dump_stats=1
@@ -1852,7 +1882,7 @@ wait_attempt_fail()
while [ $time -lt $timeout_ms ]; do
local cnt
- cnt=$(ip netns exec $ns nstat -as TcpAttemptFails | grep TcpAttemptFails | awk '{print $2}')
+ cnt=$(get_counter ${ns} "TcpAttemptFails")
[ "$cnt" = 1 ] && return 1
time=$((time + 100))