[0] 0.204.111.166.in-addr.arpa.: domain name does not exist
[0] 1.204.111.166.in-addr.arpa.: domain name does not exist
[0] 2.204.111.166.in-addr.arpa.: domain name does not exist
[0] 3.204.111.166.in-addr.arpa.: domain name does not exist
[0] 4.204.111.166.in-addr.arpa.: domain name does not exist
[0] 5.204.111.166.in-addr.arpa.: domain name does not exist
[0] 6.204.111.166.in-addr.arpa.: domain name does not exist
[0] 7.204.111.166.in-addr.arpa.: domain name does not exist
[86400] 8.204.111.166.in-addr.arpa. domain name pointer sea.net.edu.cn mail.tsinghua.edu.cn cernet.edu.cn
[86400] 9.204.111.166.in-addr.arpa. domain name pointer mails.tsinghua.edu.cn
[0] 10.204.111.166.in-addr.arpa.: domain name does not exist
[0] 11.204.111.166.in-addr.arpa.: domain name does not exist
[0] 12.204.111.166.in-addr.arpa.: domain name does not exist
[0] 13.204.111.166.in-addr.arpa.: domain name does not exist
[0] 14.204.111.166.in-addr.arpa.: domain name does not exist
[0] 15.204.111.166.in-addr.arpa.: domain name does not exist
[0] 16.204.111.166.in-addr.arpa.: domain name does not exist
[0] 17.204.111.166.in-addr.arpa.: domain name does not exist
[0] 18.204.111.166.in-addr.arpa.: domain name does not exist
[0] 19.204.111.166.in-addr.arpa.: domain name does not exist
[0] 20.204.111.166.in-addr.arpa.: domain name does not exist
[0] 21.204.111.166.in-addr.arpa.: domain name does not exist
[0] 22.204.111.166.in-addr.arpa.: domain name does not exist
[0] 23.204.111.166.in-addr.arpa.: domain name does not exist
[0] 24.204.111.166.in-addr.arpa.: domain name does not exist
[86400] 25.204.111.166.in-addr.arpa. domain name pointer smtp01.tsinghua.edu.cn
[86400] 26.204.111.166.in-addr.arpa. domain name pointer smtp02.tsinghua.edu.cn
[86400] 27.204.111.166.in-addr.arpa. domain name pointer smtp03.tsinghua.edu.cn
[86400] 28.204.111.166.in-addr.arpa. domain name pointer smtp04.tsinghua.edu.cn
[86400] 29.204.111.166.in-addr.arpa. domain name pointer smtp05.tsinghua.edu.cn
[86400] 30.204.111.166.in-addr.arpa. domain name pointer smtp06.tsinghua.edu.cn
[86400] 31.204.111.166.in-addr.arpa. domain name pointer smtp07.tsinghua.edu.cn
[86400] 32.204.111.166.in-addr.arpa. domain name pointer smtp08.tsinghua.edu.cn
[86400] 33.204.111.166.in-addr.arpa. domain name pointer smtp09.tsinghua.edu.cn
[86400] 34.204.111.166.in-addr.arpa. domain name pointer smtp10.tsinghua.edu.cn
[86400] 35.204.111.166.in-addr.arpa. domain name pointer smtp11.tsinghua.edu.cn
[86400] 36.204.111.166.in-addr.arpa. domain name pointer smtp12.tsinghua.edu.cn
[86400] 37.204.111.166.in-addr.arpa. domain name pointer smtp13.tsinghua.edu.cn
[86400] 38.204.111.166.in-addr.arpa. domain name pointer smtp14.tsinghua.edu.cn
[86400] 39.204.111.166.in-addr.arpa. domain name pointer smtp15.tsinghua.edu.cn
[86400] 40.204.111.166.in-addr.arpa. domain name pointer smtp16.tsinghua.edu.cn
[86400] 41.204.111.166.in-addr.arpa. domain name pointer smtp17.tsinghua.edu.cn
[86400] 42.204.111.166.in-addr.arpa. domain name pointer smtp18.tsinghua.edu.cn
[86400] 43.204.111.166.in-addr.arpa. domain name pointer smtp19.tsinghua.edu.cn
[86400] 44.204.111.166.in-addr.arpa. domain name pointer smtp20.tsinghua.edu.cn
[86400] 45.204.111.166.in-addr.arpa. domain name pointer smtp21.tsinghua.edu.cn
[86400] 46.204.111.166.in-addr.arpa. domain name pointer smtp22.tsinghua.edu.cn
[86400] 47.204.111.166.in-addr.arpa. domain name pointer smtp23.tsinghua.edu.cn
[86400] 48.204.111.166.in-addr.arpa. domain name pointer smtp24.tsinghua.edu.cn
[86400] 49.204.111.166.in-addr.arpa. domain name pointer smtp25.tsinghua.edu.cn
[86400] 50.204.111.166.in-addr.arpa. domain name pointer smtp26.tsinghua.edu.cn
[86400] 51.204.111.166.in-addr.arpa. domain name pointer smtp27.tsinghua.edu.cn
[86400] 52.204.111.166.in-addr.arpa. domain name pointer smtp28.tsinghua.edu.cn
[86400] 53.204.111.166.in-addr.arpa. domain name pointer smtp29.tsinghua.edu.cn
[86400] 54.204.111.166.in-addr.arpa. domain name pointer smtp30.tsinghua.edu.cn
[86400] 55.204.111.166.in-addr.arpa. domain name pointer smtp31.tsinghua.edu.cn
[86400] 56.204.111.166.in-addr.arpa. domain name pointer smtp32.tsinghua.edu.cn
[86400] 57.204.111.166.in-addr.arpa. domain name pointer smtp33.tsinghua.edu.cn
[86400] 58.204.111.166.in-addr.arpa. domain name pointer smtp34.tsinghua.edu.cn
[86400] 59.204.111.166.in-addr.arpa. domain name pointer smtp35.tsinghua.edu.cn
[86400] 60.204.111.166.in-addr.arpa. domain name pointer smtp36.tsinghua.edu.cn
[86400] 61.204.111.166.in-addr.arpa. domain name pointer smtp37.tsinghua.edu.cn
[86400] 62.204.111.166.in-addr.arpa. domain name pointer smtp38.tsinghua.edu.cn
[86400] 63.204.111.166.in-addr.arpa. domain name pointer smtp39.tsinghua.edu.cn
[86400] 64.204.111.166.in-addr.arpa. domain name pointer smtp40.tsinghua.edu.cn
[86400] 65.204.111.166.in-addr.arpa. domain name pointer smtp41.tsinghua.edu.cn
[86400] 66.204.111.166.in-addr.arpa. domain name pointer smtp42.tsinghua.edu.cn
[86400] 67.204.111.166.in-addr.arpa. domain name pointer smtp43.tsinghua.edu.cn
[86400] 68.204.111.166.in-addr.arpa. domain name pointer smtp44.tsinghua.edu.cn
[86400] 69.204.111.166.in-addr.arpa. domain name pointer smtp45.tsinghua.edu.cn
[86400] 70.204.111.166.in-addr.arpa. domain name pointer smtp46.tsinghua.edu.cn
[86400] 71.204.111.166.in-addr.arpa. domain name pointer smtp47.tsinghua.edu.cn
[86400] 72.204.111.166.in-addr.arpa. domain name pointer smtp48.tsinghua.edu.cn
[86400] 73.204.111.166.in-addr.arpa. domain name pointer smtp49.tsinghua.edu.cn
[86400] 74.204.111.166.in-addr.arpa. domain name pointer smtp50.tsinghua.edu.cn
[86400] 75.204.111.166.in-addr.arpa. domain name pointer smtp51.tsinghua.edu.cn
[86400] 76.204.111.166.in-addr.arpa. domain name pointer smtp52.tsinghua.edu.cn
[86400] 77.204.111.166.in-addr.arpa. domain name pointer smtp53.tsinghua.edu.cn
[86400] 78.204.111.166.in-addr.arpa. domain name pointer smtp54.tsinghua.edu.cn
[86400] 79.204.111.166.in-addr.arpa. domain name pointer smtp55.tsinghua.edu.cn
[86400] 80.204.111.166.in-addr.arpa. domain name pointer smtp56.tsinghua.edu.cn
[86400] 81.204.111.166.in-addr.arpa. domain name pointer smtp57.tsinghua.edu.cn
[86400] 82.204.111.166.in-addr.arpa. domain name pointer smtp58.tsinghua.edu.cn
[86400] 83.204.111.166.in-addr.arpa. domain name pointer smtp59.tsinghua.edu.cn
[86400] 84.204.111.166.in-addr.arpa. domain name pointer smtp60.tsinghua.edu.cn
[86400] 85.204.111.166.in-addr.arpa. domain name pointer smtp61.tsinghua.edu.cn
[86400] 86.204.111.166.in-addr.arpa. domain name pointer smtp62.tsinghua.edu.cn
[86400] 87.204.111.166.in-addr.arpa. domain name pointer smtp63.tsinghua.edu.cn
[86400] 88.204.111.166.in-addr.arpa. domain name pointer smtp64.tsinghua.edu.cn
[86400] 89.204.111.166.in-addr.arpa. domain name pointer smtp65.tsinghua.edu.cn
[86400] 90.204.111.166.in-addr.arpa. domain name pointer smtp66.tsinghua.edu.cn
[86400] 91.204.111.166.in-addr.arpa. domain name pointer smtp67.tsinghua.edu.cn
[86400] 92.204.111.166.in-addr.arpa. domain name pointer smtp68.tsinghua.edu.cn
[86400] 93.204.111.166.in-addr.arpa. domain name pointer smtp69.tsinghua.edu.cn
[86400] 94.204.111.166.in-addr.arpa. domain name pointer smtp70.tsinghua.edu.cn
[86400] 95.204.111.166.in-addr.arpa. domain name pointer smtp71.tsinghua.edu.cn
[86400] 96.204.111.166.in-addr.arpa. domain name pointer smtp72.tsinghua.edu.cn
[86400] 97.204.111.166.in-addr.arpa. domain name pointer smtp73.tsinghua.edu.cn
[86400] 98.204.111.166.in-addr.arpa. domain name pointer smtp74.tsinghua.edu.cn
[86400] 99.204.111.166.in-addr.arpa. domain name pointer smtp75.tsinghua.edu.cn
[86400] 100.204.111.166.in-addr.arpa. domain name pointer smtp76.tsinghua.edu.cn
[86400] 101.204.111.166.in-addr.arpa. domain name pointer smtp77.tsinghua.edu.cn
[86400] 102.204.111.166.in-addr.arpa. domain name pointer smtp78.tsinghua.edu.cn
[86400] 103.204.111.166.in-addr.arpa. domain name pointer smtp79.tsinghua.edu.cn
[86400] 104.204.111.166.in-addr.arpa. domain name pointer smtp80.tsinghua.edu.cn
[86400] 105.204.111.166.in-addr.arpa. domain name pointer smtp81.tsinghua.edu.cn
[86400] 106.204.111.166.in-addr.arpa. domain name pointer smtp82.tsinghua.edu.cn
[86400] 107.204.111.166.in-addr.arpa. domain name pointer smtp83.tsinghua.edu.cn
[86400] 108.204.111.166.in-addr.arpa. domain name pointer smtp84.tsinghua.edu.cn
[86400] 109.204.111.166.in-addr.arpa. domain name pointer smtp85.tsinghua.edu.cn
[86400] 110.204.111.166.in-addr.arpa. domain name pointer smtp86.tsinghua.edu.cn
[86400] 111.204.111.166.in-addr.arpa. domain name pointer smtp87.tsinghua.edu.cn
[86400] 112.204.111.166.in-addr.arpa. domain name pointer smtp88.tsinghua.edu.cn
[86400] 113.204.111.166.in-addr.arpa. domain name pointer smtp89.tsinghua.edu.cn
[86400] 114.204.111.166.in-addr.arpa. domain name pointer smtp90.tsinghua.edu.cn
[86400] 115.204.111.166.in-addr.arpa. domain name pointer smtp91.tsinghua.edu.cn
[86400] 116.204.111.166.in-addr.arpa. domain name pointer smtp92.tsinghua.edu.cn
[86400] 117.204.111.166.in-addr.arpa. domain name pointer smtp93.tsinghua.edu.cn
[86400] 118.204.111.166.in-addr.arpa. domain name pointer smtp94.tsinghua.edu.cn
[86400] 119.204.111.166.in-addr.arpa. domain name pointer smtp95.tsinghua.edu.cn
[86400] 120.204.111.166.in-addr.arpa. domain name pointer smtp96.tsinghua.edu.cn
[86400] 121.204.111.166.in-addr.arpa. domain name pointer smtp97.tsinghua.edu.cn
[86400] 122.204.111.166.in-addr.arpa. domain name pointer smtp98.tsinghua.edu.cn
[86400] 123.204.111.166.in-addr.arpa. domain name pointer smtp99.tsinghua.edu.cn
[86400] 124.204.111.166.in-addr.arpa. domain name pointer smtp100.tsinghua.edu.cn
[86400] 125.204.111.166.in-addr.arpa. domain name pointer smtp101.tsinghua.edu.cn
[86400] 126.204.111.166.in-addr.arpa. domain name pointer smtp102.tsinghua.edu.cn
[86400] 127.204.111.166.in-addr.arpa. domain name pointer smtp103.tsinghua.edu.cn
[86400] 128.204.111.166.in-addr.arpa. domain name pointer smtp104.tsinghua.edu.cn
[86400] 129.204.111.166.in-addr.arpa. domain name pointer smtp105.tsinghua.edu.cn
[86400] 130.204.111.166.in-addr.arpa. domain name pointer smtp106.tsinghua.edu.cn
[86400] 131.204.111.166.in-addr.arpa. domain name pointer smtp107.tsinghua.edu.cn
[86400] 132.204.111.166.in-addr.arpa. domain name pointer smtp108.tsinghua.edu.cn
[86400] 133.204.111.166.in-addr.arpa. domain name pointer smtp109.tsinghua.edu.cn
[86400] 134.204.111.166.in-addr.arpa. domain name pointer smtp110.tsinghua.edu.cn
[86400] 135.204.111.166.in-addr.arpa. domain name pointer smtp111.tsinghua.edu.cn
[86400] 136.204.111.166.in-addr.arpa. domain name pointer smtp112.tsinghua.edu.cn
[86400] 137.204.111.166.in-addr.arpa. domain name pointer smtp113.tsinghua.edu.cn
[86400] 138.204.111.166.in-addr.arpa. domain name pointer smtp114.tsinghua.edu.cn
[86400] 139.204.111.166.in-addr.arpa. domain name pointer smtp115.tsinghua.edu.cn
[86400] 140.204.111.166.in-addr.arpa. domain name pointer smtp116.tsinghua.edu.cn
[86400] 141.204.111.166.in-addr.arpa. domain name pointer smtp117.tsinghua.edu.cn
[86400] 142.204.111.166.in-addr.arpa. domain name pointer smtp118.tsinghua.edu.cn
[86400] 143.204.111.166.in-addr.arpa. domain name pointer smtp119.tsinghua.edu.cn
[86400] 144.204.111.166.in-addr.arpa. domain name pointer smtp120.tsinghua.edu.cn
[86400] 145.204.111.166.in-addr.arpa. domain name pointer smtp121.tsinghua.edu.cn
[86400] 146.204.111.166.in-addr.arpa. domain name pointer smtp122.tsinghua.edu.cn
[86400] 147.204.111.166.in-addr.arpa. domain name pointer smtp123.tsinghua.edu.cn
[86400] 148.204.111.166.in-addr.arpa. domain name pointer smtp124.tsinghua.edu.cn
[86400] 149.204.111.166.in-addr.arpa. domain name pointer smtp125.tsinghua.edu.cn
[86400] 150.204.111.166.in-addr.arpa. domain name pointer smtp126.tsinghua.edu.cn
[86400] 151.204.111.166.in-addr.arpa. domain name pointer smtp127.tsinghua.edu.cn
[86400] 152.204.111.166.in-addr.arpa. domain name pointer smtp128.tsinghua.edu.cn
[86400] 153.204.111.166.in-addr.arpa. domain name pointer smtp129.tsinghua.edu.cn
[86400] 154.204.111.166.in-addr.arpa. domain name pointer smtp130.tsinghua.edu.cn
[86400] 155.204.111.166.in-addr.arpa. domain name pointer smtp131.tsinghua.edu.cn
[86400] 156.204.111.166.in-addr.arpa. domain name pointer smtp132.tsinghua.edu.cn
[86400] 157.204.111.166.in-addr.arpa. domain name pointer smtp133.tsinghua.edu.cn
[86400] 158.204.111.166.in-addr.arpa. domain name pointer smtp134.tsinghua.edu.cn
[86400] 159.204.111.166.in-addr.arpa. domain name pointer smtp135.tsinghua.edu.cn
[86400] 160.204.111.166.in-addr.arpa. domain name pointer smtp136.tsinghua.edu.cn
[86400] 161.204.111.166.in-addr.arpa. domain name pointer smtp137.tsinghua.edu.cn
[86400] 162.204.111.166.in-addr.arpa. domain name pointer smtp138.tsinghua.edu.cn
[86400] 163.204.111.166.in-addr.arpa. domain name pointer smtp139.tsinghua.edu.cn
[86400] 164.204.111.166.in-addr.arpa. domain name pointer smtp140.tsinghua.edu.cn
[86400] 165.204.111.166.in-addr.arpa. domain name pointer smtp141.tsinghua.edu.cn
[86400] 166.204.111.166.in-addr.arpa. domain name pointer smtp142.tsinghua.edu.cn
[86400] 167.204.111.166.in-addr.arpa. domain name pointer smtp143.tsinghua.edu.cn
[86400] 168.204.111.166.in-addr.arpa. domain name pointer smtp144.tsinghua.edu.cn
[86400] 169.204.111.166.in-addr.arpa. domain name pointer smtp145.tsinghua.edu.cn
[86400] 170.204.111.166.in-addr.arpa. domain name pointer smtp146.tsinghua.edu.cn
[86400] 171.204.111.166.in-addr.arpa. domain name pointer smtp147.tsinghua.edu.cn
[86400] 172.204.111.166.in-addr.arpa. domain name pointer smtp148.tsinghua.edu.cn
[86400] 173.204.111.166.in-addr.arpa. domain name pointer smtp149.tsinghua.edu.cn
[86400] 174.204.111.166.in-addr.arpa. domain name pointer smtp150.tsinghua.edu.cn
[86400] 175.204.111.166.in-addr.arpa. domain name pointer smtp151.tsinghua.edu.cn
[86400] 176.204.111.166.in-addr.arpa. domain name pointer smtp152.tsinghua.edu.cn
[86400] 177.204.111.166.in-addr.arpa. domain name pointer smtp153.tsinghua.edu.cn
[86400] 178.204.111.166.in-addr.arpa. domain name pointer smtp154.tsinghua.edu.cn
[86400] 179.204.111.166.in-addr.arpa. domain name pointer smtp155.tsinghua.edu.cn
[86400] 180.204.111.166.in-addr.arpa. domain name pointer smtp156.tsinghua.edu.cn
[86400] 181.204.111.166.in-addr.arpa. domain name pointer smtp157.tsinghua.edu.cn
[86400] 182.204.111.166.in-addr.arpa. domain name pointer smtp158.tsinghua.edu.cn
[86400] 183.204.111.166.in-addr.arpa. domain name pointer smtp159.tsinghua.edu.cn
[86400] 184.204.111.166.in-addr.arpa. domain name pointer smtp160.tsinghua.edu.cn
[86400] 185.204.111.166.in-addr.arpa. domain name pointer smtp161.tsinghua.edu.cn
[86400] 186.204.111.166.in-addr.arpa. domain name pointer smtp162.tsinghua.edu.cn
[86400] 187.204.111.166.in-addr.arpa. domain name pointer smtp163.tsinghua.edu.cn
[86400] 188.204.111.166.in-addr.arpa. domain name pointer smtp164.tsinghua.edu.cn
[86400] 189.204.111.166.in-addr.arpa. domain name pointer smtp165.tsinghua.edu.cn
[86400] 190.204.111.166.in-addr.arpa. domain name pointer smtp166.tsinghua.edu.cn
[86400] 191.204.111.166.in-addr.arpa. domain name pointer smtp167.tsinghua.edu.cn
[86400] 192.204.111.166.in-addr.arpa. domain name pointer smtp168.tsinghua.edu.cn
[86400] 193.204.111.166.in-addr.arpa. domain name pointer smtp169.tsinghua.edu.cn
[86400] 194.204.111.166.in-addr.arpa. domain name pointer smtp170.tsinghua.edu.cn
[86400] 195.204.111.166.in-addr.arpa. domain name pointer smtp171.tsinghua.edu.cn
[86400] 196.204.111.166.in-addr.arpa. domain name pointer smtp172.tsinghua.edu.cn
[86400] 197.204.111.166.in-addr.arpa. domain name pointer smtp173.tsinghua.edu.cn
[86400] 198.204.111.166.in-addr.arpa. domain name pointer smtp174.tsinghua.edu.cn
[86400] 199.204.111.166.in-addr.arpa. domain name pointer smtp175.tsinghua.edu.cn
[86400] 200.204.111.166.in-addr.arpa. domain name pointer smtp176.tsinghua.edu.cn
[86400] 201.204.111.166.in-addr.arpa. domain name pointer smtp177.tsinghua.edu.cn
[86400] 202.204.111.166.in-addr.arpa. domain name pointer smtp178.tsinghua.edu.cn
[86400] 203.204.111.166.in-addr.arpa. domain name pointer smtp179.tsinghua.edu.cn
[86400] 204.204.111.166.in-addr.arpa. domain name pointer smtp180.tsinghua.edu.cn
[86400] 205.204.111.166.in-addr.arpa. domain name pointer smtp181.tsinghua.edu.cn
[86400] 206.204.111.166.in-addr.arpa. domain name pointer smtp182.tsinghua.edu.cn
[86400] 207.204.111.166.in-addr.arpa. domain name pointer smtp183.tsinghua.edu.cn
[86400] 208.204.111.166.in-addr.arpa. domain name pointer smtp184.tsinghua.edu.cn
[86400] 209.204.111.166.in-addr.arpa. domain name pointer smtp185.tsinghua.edu.cn
[86400] 210.204.111.166.in-addr.arpa. domain name pointer smtp186.tsinghua.edu.cn
[86400] 211.204.111.166.in-addr.arpa. domain name pointer smtp187.tsinghua.edu.cn
[86400] 212.204.111.166.in-addr.arpa. domain name pointer smtp188.tsinghua.edu.cn
[86400] 213.204.111.166.in-addr.arpa. domain name pointer smtp189.tsinghua.edu.cn
[86400] 214.204.111.166.in-addr.arpa. domain name pointer smtp190.tsinghua.edu.cn
[86400] 215.204.111.166.in-addr.arpa. domain name pointer smtp191.tsinghua.edu.cn
[86400] 216.204.111.166.in-addr.arpa. domain name pointer smtp192.tsinghua.edu.cn
[86400] 217.204.111.166.in-addr.arpa. domain name pointer smtp193.tsinghua.edu.cn
[86400] 218.204.111.166.in-addr.arpa. domain name pointer smtp194.tsinghua.edu.cn
[86400] 219.204.111.166.in-addr.arpa. domain name pointer smtp195.tsinghua.edu.cn
[86400] 220.204.111.166.in-addr.arpa. domain name pointer smtp196.tsinghua.edu.cn
[86400] 221.204.111.166.in-addr.arpa. domain name pointer smtp197.tsinghua.edu.cn
[86400] 222.204.111.166.in-addr.arpa. domain name pointer smtp198.tsinghua.edu.cn
[86400] 223.204.111.166.in-addr.arpa. domain name pointer smtp199.tsinghua.edu.cn
[86400] 224.204.111.166.in-addr.arpa. domain name pointer smtp200.tsinghua.edu.cn
[86400] 225.204.111.166.in-addr.arpa. domain name pointer smtp201.tsinghua.edu.cn
[86400] 226.204.111.166.in-addr.arpa. domain name pointer smtp202.tsinghua.edu.cn
[86400] 227.204.111.166.in-addr.arpa. domain name pointer smtp203.tsinghua.edu.cn
[86400] 228.204.111.166.in-addr.arpa. domain name pointer smtp204.tsinghua.edu.cn
[86400] 229.204.111.166.in-addr.arpa. domain name pointer smtp205.tsinghua.edu.cn
[86400] 230.204.111.166.in-addr.arpa. domain name pointer smtp206.tsinghua.edu.cn
[86400] 231.204.111.166.in-addr.arpa. domain name pointer smtp207.tsinghua.edu.cn
[86400] 232.204.111.166.in-addr.arpa. domain name pointer smtp208.tsinghua.edu.cn
[86400] 233.204.111.166.in-addr.arpa. domain name pointer smtp209.tsinghua.edu.cn
[86400] 234.204.111.166.in-addr.arpa. domain name pointer smtp210.tsinghua.edu.cn
[86400] 235.204.111.166.in-addr.arpa. domain name pointer smtp211.tsinghua.edu.cn
[86400] 236.204.111.166.in-addr.arpa. domain name pointer smtp212.tsinghua.edu.cn
[86400] 237.204.111.166.in-addr.arpa. domain name pointer smtp213.tsinghua.edu.cn
[86400] 238.204.111.166.in-addr.arpa. domain name pointer smtp214.tsinghua.edu.cn
[86400] 239.204.111.166.in-addr.arpa. domain name pointer smtp215.tsinghua.edu.cn
[86400] 240.204.111.166.in-addr.arpa. domain name pointer smtp216.tsinghua.edu.cn
[86400] 241.204.111.166.in-addr.arpa. domain name pointer smtp217.tsinghua.edu.cn
[86400] 242.204.111.166.in-addr.arpa. domain name pointer smtp218.tsinghua.edu.cn
[86400] 243.204.111.166.in-addr.arpa. domain name pointer smtp219.tsinghua.edu.cn
[86400] 244.204.111.166.in-addr.arpa. domain name pointer smtp220.tsinghua.edu.cn
[86400] 245.204.111.166.in-addr.arpa. domain name pointer smtp221.tsinghua.edu.cn
[86400] 246.204.111.166.in-addr.arpa. domain name pointer smtp222.tsinghua.edu.cn
[86400] 247.204.111.166.in-addr.arpa. domain name pointer smtp223.tsinghua.edu.cn
[86400] 248.204.111.166.in-addr.arpa. domain name pointer smtp224.tsinghua.edu.cn
[86400] 249.204.111.166.in-addr.arpa. domain name pointer smtp225.tsinghua.edu.cn
[86400] 250.204.111.166.in-addr.arpa. domain name pointer smtp226.tsinghua.edu.cn
[86400] 251.204.111.166.in-addr.arpa. domain name pointer smtp227.tsinghua.edu.cn
[86400] 252.204.111.166.in-addr.arpa. domain name pointer smtp228.tsinghua.edu.cn
[86400] 253.204.111.166.in-addr.arpa. domain name pointer smtp229.tsinghua.edu.cn
[86400] 254.204.111.166.in-addr.arpa. domain name pointer smtp230.tsinghua.edu.cn
[0] 255.204.111.166.in-addr.arpa.: domain name does not exist